Theorem remulscl 28494

Description: The surreal reals are closed under multiplication. Part of theorem 13(ii) of [Conway] p. 24. (Contributed by Scott Fenton, 16-Apr-2025.)

Assertion

Ref	Expression
remulscl	⊢ ((𝐴 ∈ ℝs ∧ 𝐵 ∈ ℝs) → (𝐴 ·s 𝐵) ∈ ℝs)

Proof of Theorem remulscl

Dummy variables 𝑥 𝑦 𝑧 𝑛 𝑚 𝑝 𝑡 𝑢 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		mulscl 28126	. . . . 5 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (𝐴 ·s 𝐵) ∈ No )
2	1	adantr 480	. . . 4 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ ((∃𝑛 ∈ ℕs (( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ 𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))})) ∧ (∃𝑚 ∈ ℕs (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))})))) → (𝐴 ·s 𝐵) ∈ No )
3		remulscllem2 28493	. . . . . . 7 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ ((𝑛 ∈ ℕs ∧ 𝑚 ∈ ℕs) ∧ ((( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚)))) → ∃𝑝 ∈ ℕs (( -us ‘𝑝) <s (𝐴 ·s 𝐵) ∧ (𝐴 ·s 𝐵) <s 𝑝))
4	3	expr 456	. . . . . 6 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ (𝑛 ∈ ℕs ∧ 𝑚 ∈ ℕs)) → (((( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚)) → ∃𝑝 ∈ ℕs (( -us ‘𝑝) <s (𝐴 ·s 𝐵) ∧ (𝐴 ·s 𝐵) <s 𝑝)))
5	4	rexlimdvva 3194	. . . . 5 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (∃𝑛 ∈ ℕs ∃𝑚 ∈ ℕs ((( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚)) → ∃𝑝 ∈ ℕs (( -us ‘𝑝) <s (𝐴 ·s 𝐵) ∧ (𝐴 ·s 𝐵) <s 𝑝)))
6		simpl 482	. . . . . . 7 ⊢ ((∃𝑛 ∈ ℕs (( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ 𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))})) → ∃𝑛 ∈ ℕs (( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛))
7		simpl 482	. . . . . . 7 ⊢ ((∃𝑚 ∈ ℕs (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))})) → ∃𝑚 ∈ ℕs (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚))
8	6, 7	anim12i 614	. . . . . 6 ⊢ (((∃𝑛 ∈ ℕs (( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ 𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))})) ∧ (∃𝑚 ∈ ℕs (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}))) → (∃𝑛 ∈ ℕs (( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ ∃𝑚 ∈ ℕs (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚)))
9		reeanv 3209	. . . . . 6 ⊢ (∃𝑛 ∈ ℕs ∃𝑚 ∈ ℕs ((( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚)) ↔ (∃𝑛 ∈ ℕs (( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ ∃𝑚 ∈ ℕs (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚)))
10	8, 9	sylibr 234	. . . . 5 ⊢ (((∃𝑛 ∈ ℕs (( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ 𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))})) ∧ (∃𝑚 ∈ ℕs (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}))) → ∃𝑛 ∈ ℕs ∃𝑚 ∈ ℕs ((( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚)))
11	5, 10	impel 505	. . . 4 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ ((∃𝑛 ∈ ℕs (( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ 𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))})) ∧ (∃𝑚 ∈ ℕs (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))})))) → ∃𝑝 ∈ ℕs (( -us ‘𝑝) <s (𝐴 ·s 𝐵) ∧ (𝐴 ·s 𝐵) <s 𝑝))
12		simpr 484	. . . . . 6 ⊢ ((∃𝑛 ∈ ℕs (( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ 𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))})) → 𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}))
13		simpr 484	. . . . . 6 ⊢ ((∃𝑚 ∈ ℕs (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))})) → 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}))
14	12, 13	anim12i 614	. . . . 5 ⊢ (((∃𝑛 ∈ ℕs (( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ 𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))})) ∧ (∃𝑚 ∈ ℕs (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}))) → (𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))})))
15		recut 28486	. . . . . . . . 9 ⊢ (𝐴 ∈ No → {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} <<s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))})
16	15	adantr 480	. . . . . . . 8 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} <<s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))})
17	16	adantr 480	. . . . . . 7 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ (𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}))) → {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} <<s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))})
18		recut 28486	. . . . . . . 8 ⊢ (𝐵 ∈ No → {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} <<s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))})
19	18	ad2antlr 728	. . . . . . 7 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ (𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}))) → {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} <<s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))})
20		simprl 771	. . . . . . 7 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ (𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}))) → 𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}))
21		simprr 773	. . . . . . 7 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ (𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}))) → 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}))
22	17, 19, 20, 21	mulsunif2 28162	. . . . . 6 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ (𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}))) → (𝐴 ·s 𝐵) = (({𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))} ∪ {𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))}) |s ({𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))} ∪ {𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))})))
23		r19.41v 3167	. . . . . . . . . . . . . 14 ⊢ (∃𝑛 ∈ ℕs (𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))) ↔ (∃𝑛 ∈ ℕs 𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))))
24	23	exbii 1850	. . . . . . . . . . . . 13 ⊢ (∃𝑡∃𝑛 ∈ ℕs (𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑡(∃𝑛 ∈ ℕs 𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))))
25		rexcom4 3264	. . . . . . . . . . . . 13 ⊢ (∃𝑛 ∈ ℕs ∃𝑡(𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑡∃𝑛 ∈ ℕs (𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))))
26		eqeq1 2740	. . . . . . . . . . . . . . 15 ⊢ (𝑥 = 𝑡 → (𝑥 = (𝐴 -s ( 1s /su 𝑛)) ↔ 𝑡 = (𝐴 -s ( 1s /su 𝑛))))
27	26	rexbidv 3161	. . . . . . . . . . . . . 14 ⊢ (𝑥 = 𝑡 → (∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛)) ↔ ∃𝑛 ∈ ℕs 𝑡 = (𝐴 -s ( 1s /su 𝑛))))
28	27	rexab 3641	. . . . . . . . . . . . 13 ⊢ (∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢))) ↔ ∃𝑡(∃𝑛 ∈ ℕs 𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))))
29	24, 25, 28	3bitr4ri 304	. . . . . . . . . . . 12 ⊢ (∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢))) ↔ ∃𝑛 ∈ ℕs ∃𝑡(𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))))
30		ovex 7400	. . . . . . . . . . . . . . . . 17 ⊢ (𝐴 -s ( 1s /su 𝑛)) ∈ V
31		oveq2 7375	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (𝑡 = (𝐴 -s ( 1s /su 𝑛)) → (𝐴 -s 𝑡) = (𝐴 -s (𝐴 -s ( 1s /su 𝑛))))
32	31	oveq1d 7382	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝑡 = (𝐴 -s ( 1s /su 𝑛)) → ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)) = ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢)))
33	32	oveq2d 7383	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑡 = (𝐴 -s ( 1s /su 𝑛)) → ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢))) = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢))))
34	33	eqeq2d 2747	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑡 = (𝐴 -s ( 1s /su 𝑛)) → (𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢))) ↔ 𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢)))))
35	34	rexbidv 3161	. . . . . . . . . . . . . . . . 17 ⊢ (𝑡 = (𝐴 -s ( 1s /su 𝑛)) → (∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢))) ↔ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢)))))
36	30, 35	ceqsexv 3478	. . . . . . . . . . . . . . . 16 ⊢ (∃𝑡(𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢))))
37		r19.41v 3167	. . . . . . . . . . . . . . . . . 18 ⊢ (∃𝑚 ∈ ℕs (𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢)))) ↔ (∃𝑚 ∈ ℕs 𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢)))))
38	37	exbii 1850	. . . . . . . . . . . . . . . . 17 ⊢ (∃𝑢∃𝑚 ∈ ℕs (𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑢(∃𝑚 ∈ ℕs 𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢)))))
39		rexcom4 3264	. . . . . . . . . . . . . . . . 17 ⊢ (∃𝑚 ∈ ℕs ∃𝑢(𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑢∃𝑚 ∈ ℕs (𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢)))))
40		eqeq1 2740	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑦 = 𝑢 → (𝑦 = (𝐵 -s ( 1s /su 𝑚)) ↔ 𝑢 = (𝐵 -s ( 1s /su 𝑚))))
41	40	rexbidv 3161	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑦 = 𝑢 → (∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚)) ↔ ∃𝑚 ∈ ℕs 𝑢 = (𝐵 -s ( 1s /su 𝑚))))
42	41	rexab 3641	. . . . . . . . . . . . . . . . 17 ⊢ (∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢))) ↔ ∃𝑢(∃𝑚 ∈ ℕs 𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢)))))
43	38, 39, 42	3bitr4ri 304	. . . . . . . . . . . . . . . 16 ⊢ (∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢))) ↔ ∃𝑚 ∈ ℕs ∃𝑢(𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢)))))
44	36, 43	bitri 275	. . . . . . . . . . . . . . 15 ⊢ (∃𝑡(𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑚 ∈ ℕs ∃𝑢(𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢)))))
45		ovex 7400	. . . . . . . . . . . . . . . . . 18 ⊢ (𝐵 -s ( 1s /su 𝑚)) ∈ V
46		oveq2 7375	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (𝑢 = (𝐵 -s ( 1s /su 𝑚)) → (𝐵 -s 𝑢) = (𝐵 -s (𝐵 -s ( 1s /su 𝑚))))
47	46	oveq2d 7383	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝑢 = (𝐵 -s ( 1s /su 𝑚)) → ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢)) = ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s (𝐵 -s ( 1s /su 𝑚)))))
48	47	oveq2d 7383	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑢 = (𝐵 -s ( 1s /su 𝑚)) → ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢))) = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s (𝐵 -s ( 1s /su 𝑚))))))
49	48	eqeq2d 2747	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑢 = (𝐵 -s ( 1s /su 𝑚)) → (𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢))) ↔ 𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s (𝐵 -s ( 1s /su 𝑚)))))))
50	45, 49	ceqsexv 3478	. . . . . . . . . . . . . . . . 17 ⊢ (∃𝑢(𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢)))) ↔ 𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s (𝐵 -s ( 1s /su 𝑚))))))
51		simplll 775	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → 𝐴 ∈ No )
52		1no 27802	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ 1s ∈ No
53	52	a1i 11	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → 1s ∈ No )
54		nnno 28316	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (𝑛 ∈ ℕs → 𝑛 ∈ No )
55	54	ad2antlr 728	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → 𝑛 ∈ No )
56		nnne0s 28329	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (𝑛 ∈ ℕs → 𝑛 ≠ 0s )
57	56	ad2antlr 728	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → 𝑛 ≠ 0s )
58	53, 55, 57	divscld 28216	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → ( 1s /su 𝑛) ∈ No )
59	51, 58	nncansd 28089	. . . . . . . . . . . . . . . . . . . 20 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → (𝐴 -s (𝐴 -s ( 1s /su 𝑛))) = ( 1s /su 𝑛))
60		simpllr 776	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → 𝐵 ∈ No )
61		nnno 28316	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (𝑚 ∈ ℕs → 𝑚 ∈ No )
62	61	adantl 481	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → 𝑚 ∈ No )
63		nnne0s 28329	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (𝑚 ∈ ℕs → 𝑚 ≠ 0s )
64	63	adantl 481	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → 𝑚 ≠ 0s )
65	53, 62, 64	divscld 28216	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → ( 1s /su 𝑚) ∈ No )
66	60, 65	nncansd 28089	. . . . . . . . . . . . . . . . . . . 20 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → (𝐵 -s (𝐵 -s ( 1s /su 𝑚))) = ( 1s /su 𝑚))
67	59, 66	oveq12d 7385	. . . . . . . . . . . . . . . . . . 19 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s (𝐵 -s ( 1s /su 𝑚)))) = (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))
68	67	oveq2d 7383	. . . . . . . . . . . . . . . . . 18 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s (𝐵 -s ( 1s /su 𝑚))))) = ((𝐴 ·s 𝐵) -s (( 1s /su 𝑛) ·s ( 1s /su 𝑚))))
69	68	eqeq2d 2747	. . . . . . . . . . . . . . . . 17 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → (𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s (𝐵 -s ( 1s /su 𝑚))))) ↔ 𝑧 = ((𝐴 ·s 𝐵) -s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
70	50, 69	bitrid 283	. . . . . . . . . . . . . . . 16 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → (∃𝑢(𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢)))) ↔ 𝑧 = ((𝐴 ·s 𝐵) -s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
71	70	rexbidva 3159	. . . . . . . . . . . . . . 15 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) → (∃𝑚 ∈ ℕs ∃𝑢(𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑚 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
72	44, 71	bitrid 283	. . . . . . . . . . . . . 14 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) → (∃𝑡(𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑚 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
73	72	rexbidva 3159	. . . . . . . . . . . . 13 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (∃𝑛 ∈ ℕs ∃𝑡(𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑛 ∈ ℕs ∃𝑚 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
74		remulscllem1 28492	. . . . . . . . . . . . 13 ⊢ (∃𝑛 ∈ ℕs ∃𝑚 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s (( 1s /su 𝑛) ·s ( 1s /su 𝑚))) ↔ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝)))
75	73, 74	bitrdi 287	. . . . . . . . . . . 12 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (∃𝑛 ∈ ℕs ∃𝑡(𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))))
76	29, 75	bitrid 283	. . . . . . . . . . 11 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢))) ↔ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))))
77	76	abbidv 2802	. . . . . . . . . 10 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → {𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))} = {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))})
78		r19.41v 3167	. . . . . . . . . . . . . 14 ⊢ (∃𝑛 ∈ ℕs (𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))) ↔ (∃𝑛 ∈ ℕs 𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))))
79	78	exbii 1850	. . . . . . . . . . . . 13 ⊢ (∃𝑡∃𝑛 ∈ ℕs (𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑡(∃𝑛 ∈ ℕs 𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))))
80		rexcom4 3264	. . . . . . . . . . . . 13 ⊢ (∃𝑛 ∈ ℕs ∃𝑡(𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑡∃𝑛 ∈ ℕs (𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))))
81		eqeq1 2740	. . . . . . . . . . . . . . 15 ⊢ (𝑥 = 𝑡 → (𝑥 = (𝐴 +s ( 1s /su 𝑛)) ↔ 𝑡 = (𝐴 +s ( 1s /su 𝑛))))
82	81	rexbidv 3161	. . . . . . . . . . . . . 14 ⊢ (𝑥 = 𝑡 → (∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛)) ↔ ∃𝑛 ∈ ℕs 𝑡 = (𝐴 +s ( 1s /su 𝑛))))
83	82	rexab 3641	. . . . . . . . . . . . 13 ⊢ (∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵))) ↔ ∃𝑡(∃𝑛 ∈ ℕs 𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))))
84	79, 80, 83	3bitr4ri 304	. . . . . . . . . . . 12 ⊢ (∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵))) ↔ ∃𝑛 ∈ ℕs ∃𝑡(𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))))
85		ovex 7400	. . . . . . . . . . . . . . . . 17 ⊢ (𝐴 +s ( 1s /su 𝑛)) ∈ V
86		oveq1 7374	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (𝑡 = (𝐴 +s ( 1s /su 𝑛)) → (𝑡 -s 𝐴) = ((𝐴 +s ( 1s /su 𝑛)) -s 𝐴))
87	86	oveq1d 7382	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝑡 = (𝐴 +s ( 1s /su 𝑛)) → ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)) = (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵)))
88	87	oveq2d 7383	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑡 = (𝐴 +s ( 1s /su 𝑛)) → ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵))) = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵))))
89	88	eqeq2d 2747	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑡 = (𝐴 +s ( 1s /su 𝑛)) → (𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵))) ↔ 𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵)))))
90	89	rexbidv 3161	. . . . . . . . . . . . . . . . 17 ⊢ (𝑡 = (𝐴 +s ( 1s /su 𝑛)) → (∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵))) ↔ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵)))))
91	85, 90	ceqsexv 3478	. . . . . . . . . . . . . . . 16 ⊢ (∃𝑡(𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵))))
92		r19.41v 3167	. . . . . . . . . . . . . . . . . 18 ⊢ (∃𝑚 ∈ ℕs (𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵)))) ↔ (∃𝑚 ∈ ℕs 𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵)))))
93	92	exbii 1850	. . . . . . . . . . . . . . . . 17 ⊢ (∃𝑢∃𝑚 ∈ ℕs (𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑢(∃𝑚 ∈ ℕs 𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵)))))
94		rexcom4 3264	. . . . . . . . . . . . . . . . 17 ⊢ (∃𝑚 ∈ ℕs ∃𝑢(𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑢∃𝑚 ∈ ℕs (𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵)))))
95		eqeq1 2740	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑦 = 𝑢 → (𝑦 = (𝐵 +s ( 1s /su 𝑚)) ↔ 𝑢 = (𝐵 +s ( 1s /su 𝑚))))
96	95	rexbidv 3161	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑦 = 𝑢 → (∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚)) ↔ ∃𝑚 ∈ ℕs 𝑢 = (𝐵 +s ( 1s /su 𝑚))))
97	96	rexab 3641	. . . . . . . . . . . . . . . . 17 ⊢ (∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵))) ↔ ∃𝑢(∃𝑚 ∈ ℕs 𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵)))))
98	93, 94, 97	3bitr4ri 304	. . . . . . . . . . . . . . . 16 ⊢ (∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵))) ↔ ∃𝑚 ∈ ℕs ∃𝑢(𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵)))))
99	91, 98	bitri 275	. . . . . . . . . . . . . . 15 ⊢ (∃𝑡(𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑚 ∈ ℕs ∃𝑢(𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵)))))
100		ovex 7400	. . . . . . . . . . . . . . . . . 18 ⊢ (𝐵 +s ( 1s /su 𝑚)) ∈ V
101		oveq1 7374	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (𝑢 = (𝐵 +s ( 1s /su 𝑚)) → (𝑢 -s 𝐵) = ((𝐵 +s ( 1s /su 𝑚)) -s 𝐵))
102	101	oveq2d 7383	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝑢 = (𝐵 +s ( 1s /su 𝑚)) → (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵)) = (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s ((𝐵 +s ( 1s /su 𝑚)) -s 𝐵)))
103	102	oveq2d 7383	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑢 = (𝐵 +s ( 1s /su 𝑚)) → ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵))) = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s ((𝐵 +s ( 1s /su 𝑚)) -s 𝐵))))
104	103	eqeq2d 2747	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑢 = (𝐵 +s ( 1s /su 𝑚)) → (𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵))) ↔ 𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s ((𝐵 +s ( 1s /su 𝑚)) -s 𝐵)))))
105	100, 104	ceqsexv 3478	. . . . . . . . . . . . . . . . 17 ⊢ (∃𝑢(𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵)))) ↔ 𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s ((𝐵 +s ( 1s /su 𝑚)) -s 𝐵))))
106		pncan2s 28066	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ((𝐴 ∈ No ∧ ( 1s /su 𝑛) ∈ No ) → ((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) = ( 1s /su 𝑛))
107	51, 58, 106	syl2anc 585	. . . . . . . . . . . . . . . . . . . 20 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → ((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) = ( 1s /su 𝑛))
108		pncan2s 28066	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ((𝐵 ∈ No ∧ ( 1s /su 𝑚) ∈ No ) → ((𝐵 +s ( 1s /su 𝑚)) -s 𝐵) = ( 1s /su 𝑚))
109	60, 65, 108	syl2anc 585	. . . . . . . . . . . . . . . . . . . 20 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → ((𝐵 +s ( 1s /su 𝑚)) -s 𝐵) = ( 1s /su 𝑚))
110	107, 109	oveq12d 7385	. . . . . . . . . . . . . . . . . . 19 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s ((𝐵 +s ( 1s /su 𝑚)) -s 𝐵)) = (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))
111	110	oveq2d 7383	. . . . . . . . . . . . . . . . . 18 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s ((𝐵 +s ( 1s /su 𝑚)) -s 𝐵))) = ((𝐴 ·s 𝐵) -s (( 1s /su 𝑛) ·s ( 1s /su 𝑚))))
112	111	eqeq2d 2747	. . . . . . . . . . . . . . . . 17 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → (𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s ((𝐵 +s ( 1s /su 𝑚)) -s 𝐵))) ↔ 𝑧 = ((𝐴 ·s 𝐵) -s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
113	105, 112	bitrid 283	. . . . . . . . . . . . . . . 16 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → (∃𝑢(𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵)))) ↔ 𝑧 = ((𝐴 ·s 𝐵) -s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
114	113	rexbidva 3159	. . . . . . . . . . . . . . 15 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) → (∃𝑚 ∈ ℕs ∃𝑢(𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) -s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑚 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
115	99, 114	bitrid 283	. . . . . . . . . . . . . 14 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) → (∃𝑡(𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑚 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
116	115	rexbidva 3159	. . . . . . . . . . . . 13 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (∃𝑛 ∈ ℕs ∃𝑡(𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑛 ∈ ℕs ∃𝑚 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
117	116, 74	bitrdi 287	. . . . . . . . . . . 12 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (∃𝑛 ∈ ℕs ∃𝑡(𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))))
118	84, 117	bitrid 283	. . . . . . . . . . 11 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵))) ↔ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))))
119	118	abbidv 2802	. . . . . . . . . 10 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → {𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))} = {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))})
120	77, 119	uneq12d 4109	. . . . . . . . 9 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → ({𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))} ∪ {𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))}) = ({𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))} ∪ {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))}))
121		unidm 4097	. . . . . . . . 9 ⊢ ({𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))} ∪ {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))}) = {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))}
122	120, 121	eqtrdi 2787	. . . . . . . 8 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → ({𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))} ∪ {𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))}) = {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))})
123		r19.41v 3167	. . . . . . . . . . . . . 14 ⊢ (∃𝑛 ∈ ℕs (𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))) ↔ (∃𝑛 ∈ ℕs 𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))))
124	123	exbii 1850	. . . . . . . . . . . . 13 ⊢ (∃𝑡∃𝑛 ∈ ℕs (𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑡(∃𝑛 ∈ ℕs 𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))))
125		rexcom4 3264	. . . . . . . . . . . . 13 ⊢ (∃𝑛 ∈ ℕs ∃𝑡(𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑡∃𝑛 ∈ ℕs (𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))))
126	27	rexab 3641	. . . . . . . . . . . . 13 ⊢ (∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵))) ↔ ∃𝑡(∃𝑛 ∈ ℕs 𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))))
127	124, 125, 126	3bitr4ri 304	. . . . . . . . . . . 12 ⊢ (∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵))) ↔ ∃𝑛 ∈ ℕs ∃𝑡(𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))))
128	31	oveq1d 7382	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝑡 = (𝐴 -s ( 1s /su 𝑛)) → ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)) = ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵)))
129	128	oveq2d 7383	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑡 = (𝐴 -s ( 1s /su 𝑛)) → ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵))) = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵))))
130	129	eqeq2d 2747	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑡 = (𝐴 -s ( 1s /su 𝑛)) → (𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵))) ↔ 𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵)))))
131	130	rexbidv 3161	. . . . . . . . . . . . . . . . 17 ⊢ (𝑡 = (𝐴 -s ( 1s /su 𝑛)) → (∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵))) ↔ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵)))))
132	30, 131	ceqsexv 3478	. . . . . . . . . . . . . . . 16 ⊢ (∃𝑡(𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵))))
133		r19.41v 3167	. . . . . . . . . . . . . . . . . 18 ⊢ (∃𝑚 ∈ ℕs (𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵)))) ↔ (∃𝑚 ∈ ℕs 𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵)))))
134	133	exbii 1850	. . . . . . . . . . . . . . . . 17 ⊢ (∃𝑢∃𝑚 ∈ ℕs (𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑢(∃𝑚 ∈ ℕs 𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵)))))
135		rexcom4 3264	. . . . . . . . . . . . . . . . 17 ⊢ (∃𝑚 ∈ ℕs ∃𝑢(𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑢∃𝑚 ∈ ℕs (𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵)))))
136	96	rexab 3641	. . . . . . . . . . . . . . . . 17 ⊢ (∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵))) ↔ ∃𝑢(∃𝑚 ∈ ℕs 𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵)))))
137	134, 135, 136	3bitr4ri 304	. . . . . . . . . . . . . . . 16 ⊢ (∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵))) ↔ ∃𝑚 ∈ ℕs ∃𝑢(𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵)))))
138	132, 137	bitri 275	. . . . . . . . . . . . . . 15 ⊢ (∃𝑡(𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑚 ∈ ℕs ∃𝑢(𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵)))))
139	101	oveq2d 7383	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝑢 = (𝐵 +s ( 1s /su 𝑚)) → ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵)) = ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s ((𝐵 +s ( 1s /su 𝑚)) -s 𝐵)))
140	139	oveq2d 7383	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑢 = (𝐵 +s ( 1s /su 𝑚)) → ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵))) = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s ((𝐵 +s ( 1s /su 𝑚)) -s 𝐵))))
141	140	eqeq2d 2747	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑢 = (𝐵 +s ( 1s /su 𝑚)) → (𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵))) ↔ 𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s ((𝐵 +s ( 1s /su 𝑚)) -s 𝐵)))))
142	100, 141	ceqsexv 3478	. . . . . . . . . . . . . . . . 17 ⊢ (∃𝑢(𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵)))) ↔ 𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s ((𝐵 +s ( 1s /su 𝑚)) -s 𝐵))))
143	59, 109	oveq12d 7385	. . . . . . . . . . . . . . . . . . 19 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s ((𝐵 +s ( 1s /su 𝑚)) -s 𝐵)) = (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))
144	143	oveq2d 7383	. . . . . . . . . . . . . . . . . 18 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s ((𝐵 +s ( 1s /su 𝑚)) -s 𝐵))) = ((𝐴 ·s 𝐵) +s (( 1s /su 𝑛) ·s ( 1s /su 𝑚))))
145	144	eqeq2d 2747	. . . . . . . . . . . . . . . . 17 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → (𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s ((𝐵 +s ( 1s /su 𝑚)) -s 𝐵))) ↔ 𝑧 = ((𝐴 ·s 𝐵) +s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
146	142, 145	bitrid 283	. . . . . . . . . . . . . . . 16 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → (∃𝑢(𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵)))) ↔ 𝑧 = ((𝐴 ·s 𝐵) +s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
147	146	rexbidva 3159	. . . . . . . . . . . . . . 15 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) → (∃𝑚 ∈ ℕs ∃𝑢(𝑢 = (𝐵 +s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s (𝐴 -s ( 1s /su 𝑛))) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑚 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
148	138, 147	bitrid 283	. . . . . . . . . . . . . 14 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) → (∃𝑡(𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑚 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
149	148	rexbidva 3159	. . . . . . . . . . . . 13 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (∃𝑛 ∈ ℕs ∃𝑡(𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑛 ∈ ℕs ∃𝑚 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
150		remulscllem1 28492	. . . . . . . . . . . . 13 ⊢ (∃𝑛 ∈ ℕs ∃𝑚 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s (( 1s /su 𝑛) ·s ( 1s /su 𝑚))) ↔ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝)))
151	149, 150	bitrdi 287	. . . . . . . . . . . 12 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (∃𝑛 ∈ ℕs ∃𝑡(𝑡 = (𝐴 -s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))) ↔ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))))
152	127, 151	bitrid 283	. . . . . . . . . . 11 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵))) ↔ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))))
153	152	abbidv 2802	. . . . . . . . . 10 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → {𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))} = {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))})
154		r19.41v 3167	. . . . . . . . . . . . . 14 ⊢ (∃𝑛 ∈ ℕs (𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))) ↔ (∃𝑛 ∈ ℕs 𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))))
155	154	exbii 1850	. . . . . . . . . . . . 13 ⊢ (∃𝑡∃𝑛 ∈ ℕs (𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑡(∃𝑛 ∈ ℕs 𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))))
156		rexcom4 3264	. . . . . . . . . . . . 13 ⊢ (∃𝑛 ∈ ℕs ∃𝑡(𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑡∃𝑛 ∈ ℕs (𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))))
157	82	rexab 3641	. . . . . . . . . . . . 13 ⊢ (∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢))) ↔ ∃𝑡(∃𝑛 ∈ ℕs 𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))))
158	155, 156, 157	3bitr4ri 304	. . . . . . . . . . . 12 ⊢ (∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢))) ↔ ∃𝑛 ∈ ℕs ∃𝑡(𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))))
159	86	oveq1d 7382	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝑡 = (𝐴 +s ( 1s /su 𝑛)) → ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)) = (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢)))
160	159	oveq2d 7383	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑡 = (𝐴 +s ( 1s /su 𝑛)) → ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢))) = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢))))
161	160	eqeq2d 2747	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑡 = (𝐴 +s ( 1s /su 𝑛)) → (𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢))) ↔ 𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢)))))
162	161	rexbidv 3161	. . . . . . . . . . . . . . . . 17 ⊢ (𝑡 = (𝐴 +s ( 1s /su 𝑛)) → (∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢))) ↔ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢)))))
163	85, 162	ceqsexv 3478	. . . . . . . . . . . . . . . 16 ⊢ (∃𝑡(𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢))))
164		r19.41v 3167	. . . . . . . . . . . . . . . . . 18 ⊢ (∃𝑚 ∈ ℕs (𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢)))) ↔ (∃𝑚 ∈ ℕs 𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢)))))
165	164	exbii 1850	. . . . . . . . . . . . . . . . 17 ⊢ (∃𝑢∃𝑚 ∈ ℕs (𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑢(∃𝑚 ∈ ℕs 𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢)))))
166		rexcom4 3264	. . . . . . . . . . . . . . . . 17 ⊢ (∃𝑚 ∈ ℕs ∃𝑢(𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑢∃𝑚 ∈ ℕs (𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢)))))
167	41	rexab 3641	. . . . . . . . . . . . . . . . 17 ⊢ (∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢))) ↔ ∃𝑢(∃𝑚 ∈ ℕs 𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢)))))
168	165, 166, 167	3bitr4ri 304	. . . . . . . . . . . . . . . 16 ⊢ (∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢))) ↔ ∃𝑚 ∈ ℕs ∃𝑢(𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢)))))
169	163, 168	bitri 275	. . . . . . . . . . . . . . 15 ⊢ (∃𝑡(𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑚 ∈ ℕs ∃𝑢(𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢)))))
170	46	oveq2d 7383	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝑢 = (𝐵 -s ( 1s /su 𝑚)) → (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢)) = (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s (𝐵 -s ( 1s /su 𝑚)))))
171	170	oveq2d 7383	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑢 = (𝐵 -s ( 1s /su 𝑚)) → ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢))) = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s (𝐵 -s ( 1s /su 𝑚))))))
172	171	eqeq2d 2747	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑢 = (𝐵 -s ( 1s /su 𝑚)) → (𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢))) ↔ 𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s (𝐵 -s ( 1s /su 𝑚)))))))
173	45, 172	ceqsexv 3478	. . . . . . . . . . . . . . . . 17 ⊢ (∃𝑢(𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢)))) ↔ 𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s (𝐵 -s ( 1s /su 𝑚))))))
174	107, 66	oveq12d 7385	. . . . . . . . . . . . . . . . . . 19 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s (𝐵 -s ( 1s /su 𝑚)))) = (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))
175	174	oveq2d 7383	. . . . . . . . . . . . . . . . . 18 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s (𝐵 -s ( 1s /su 𝑚))))) = ((𝐴 ·s 𝐵) +s (( 1s /su 𝑛) ·s ( 1s /su 𝑚))))
176	175	eqeq2d 2747	. . . . . . . . . . . . . . . . 17 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → (𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s (𝐵 -s ( 1s /su 𝑚))))) ↔ 𝑧 = ((𝐴 ·s 𝐵) +s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
177	173, 176	bitrid 283	. . . . . . . . . . . . . . . 16 ⊢ ((((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs) → (∃𝑢(𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢)))) ↔ 𝑧 = ((𝐴 ·s 𝐵) +s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
178	177	rexbidva 3159	. . . . . . . . . . . . . . 15 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) → (∃𝑚 ∈ ℕs ∃𝑢(𝑢 = (𝐵 -s ( 1s /su 𝑚)) ∧ 𝑧 = ((𝐴 ·s 𝐵) +s (((𝐴 +s ( 1s /su 𝑛)) -s 𝐴) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑚 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
179	169, 178	bitrid 283	. . . . . . . . . . . . . 14 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ 𝑛 ∈ ℕs) → (∃𝑡(𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑚 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
180	179	rexbidva 3159	. . . . . . . . . . . . 13 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (∃𝑛 ∈ ℕs ∃𝑡(𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑛 ∈ ℕs ∃𝑚 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s (( 1s /su 𝑛) ·s ( 1s /su 𝑚)))))
181	180, 150	bitrdi 287	. . . . . . . . . . . 12 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (∃𝑛 ∈ ℕs ∃𝑡(𝑡 = (𝐴 +s ( 1s /su 𝑛)) ∧ ∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))) ↔ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))))
182	158, 181	bitrid 283	. . . . . . . . . . 11 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢))) ↔ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))))
183	182	abbidv 2802	. . . . . . . . . 10 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → {𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))} = {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))})
184	153, 183	uneq12d 4109	. . . . . . . . 9 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → ({𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))} ∪ {𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))}) = ({𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))} ∪ {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))}))
185		unidm 4097	. . . . . . . . 9 ⊢ ({𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))} ∪ {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))}) = {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))}
186	184, 185	eqtrdi 2787	. . . . . . . 8 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → ({𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))} ∪ {𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))}) = {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))})
187	122, 186	oveq12d 7385	. . . . . . 7 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (({𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))} ∪ {𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))}) |s ({𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))} ∪ {𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))})) = ({𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))} |s {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))}))
188	187	adantr 480	. . . . . 6 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ (𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}))) → (({𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝐴 -s 𝑡) ·s (𝐵 -s 𝑢)))} ∪ {𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) -s ((𝑡 -s 𝐴) ·s (𝑢 -s 𝐵)))}) |s ({𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝐴 -s 𝑡) ·s (𝑢 -s 𝐵)))} ∪ {𝑧 ∣ ∃𝑡 ∈ {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}∃𝑢 ∈ {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))}𝑧 = ((𝐴 ·s 𝐵) +s ((𝑡 -s 𝐴) ·s (𝐵 -s 𝑢)))})) = ({𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))} |s {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))}))
189	22, 188	eqtrd 2771	. . . . 5 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ (𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}))) → (𝐴 ·s 𝐵) = ({𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))} |s {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))}))
190	14, 189	sylan2 594	. . . 4 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ ((∃𝑛 ∈ ℕs (( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ 𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))})) ∧ (∃𝑚 ∈ ℕs (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))})))) → (𝐴 ·s 𝐵) = ({𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))} |s {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))}))
191	2, 11, 190	jca32 515	. . 3 ⊢ (((𝐴 ∈ No ∧ 𝐵 ∈ No ) ∧ ((∃𝑛 ∈ ℕs (( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ 𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))})) ∧ (∃𝑚 ∈ ℕs (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))})))) → ((𝐴 ·s 𝐵) ∈ No ∧ (∃𝑝 ∈ ℕs (( -us ‘𝑝) <s (𝐴 ·s 𝐵) ∧ (𝐴 ·s 𝐵) <s 𝑝) ∧ (𝐴 ·s 𝐵) = ({𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))} |s {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))}))))
192	191	an4s 661	. 2 ⊢ (((𝐴 ∈ No ∧ (∃𝑛 ∈ ℕs (( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ 𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}))) ∧ (𝐵 ∈ No ∧ (∃𝑚 ∈ ℕs (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))})))) → ((𝐴 ·s 𝐵) ∈ No ∧ (∃𝑝 ∈ ℕs (( -us ‘𝑝) <s (𝐴 ·s 𝐵) ∧ (𝐴 ·s 𝐵) <s 𝑝) ∧ (𝐴 ·s 𝐵) = ({𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))} |s {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))}))))
193		elreno 28483	. . 3 ⊢ (𝐴 ∈ ℝs ↔ (𝐴 ∈ No ∧ (∃𝑛 ∈ ℕs (( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ 𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}))))
194		elreno 28483	. . 3 ⊢ (𝐵 ∈ ℝs ↔ (𝐵 ∈ No ∧ (∃𝑚 ∈ ℕs (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))}))))
195	193, 194	anbi12i 629	. 2 ⊢ ((𝐴 ∈ ℝs ∧ 𝐵 ∈ ℝs) ↔ ((𝐴 ∈ No ∧ (∃𝑛 ∈ ℕs (( -us ‘𝑛) <s 𝐴 ∧ 𝐴 <s 𝑛) ∧ 𝐴 = ({𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s /su 𝑛))} |s {𝑥 ∣ ∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s /su 𝑛))}))) ∧ (𝐵 ∈ No ∧ (∃𝑚 ∈ ℕs (( -us ‘𝑚) <s 𝐵 ∧ 𝐵 <s 𝑚) ∧ 𝐵 = ({𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s /su 𝑚))} |s {𝑦 ∣ ∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s /su 𝑚))})))))
196		elreno 28483	. 2 ⊢ ((𝐴 ·s 𝐵) ∈ ℝs ↔ ((𝐴 ·s 𝐵) ∈ No ∧ (∃𝑝 ∈ ℕs (( -us ‘𝑝) <s (𝐴 ·s 𝐵) ∧ (𝐴 ·s 𝐵) <s 𝑝) ∧ (𝐴 ·s 𝐵) = ({𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) -s ( 1s /su 𝑝))} |s {𝑧 ∣ ∃𝑝 ∈ ℕs 𝑧 = ((𝐴 ·s 𝐵) +s ( 1s /su 𝑝))}))))
197	192, 195, 196	3imtr4i 292	1 ⊢ ((𝐴 ∈ ℝs ∧ 𝐵 ∈ ℝs) → (𝐴 ·s 𝐵) ∈ ℝs)

Syntax hints:   → wi 4   ∧ wa 395   = wceq 1542  ∃wex 1781   ∈ wcel 2114  {cab 2714   ≠ wne 2932  ∃wrex 3061   ∪ cun 3887   class class class wbr 5085  ‘cfv 6498  (class class class)co 7367   No csur 27603   <s clts 27604   <<s cslts 27749   |s ccuts 27751   0_s c0s 27797   1_s c1s 27798   +_s cadds 27951   -u_s cnegs 28011   -_s csubs 28012   ·_s cmuls 28098   /_su cdivs 28179  ℕ_scnns 28305  ℝ_screno 28481

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1912  ax-6 1969  ax-7 2010  ax-8 2116  ax-9 2124  ax-10 2147  ax-11 2163  ax-12 2185  ax-ext 2708  ax-rep 5212  ax-sep 5231  ax-nul 5241  ax-pow 5307  ax-pr 5375  ax-un 7689  ax-inf2 9562  ax-dc 10368

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3or 1088  df-3an 1089  df-tru 1545  df-fal 1555  df-ex 1782  df-nf 1786  df-sb 2069  df-mo 2539  df-eu 2569  df-clab 2715  df-cleq 2728  df-clel 2811  df-nfc 2885  df-ne 2933  df-ral 3052  df-rex 3062  df-rmo 3342  df-reu 3343  df-rab 3390  df-v 3431  df-sbc 3729  df-csb 3838  df-dif 3892  df-un 3894  df-in 3896  df-ss 3906  df-pss 3909  df-nul 4274  df-if 4467  df-pw 4543  df-sn 4568  df-pr 4570  df-tp 4572  df-op 4574  df-ot 4576  df-uni 4851  df-int 4890  df-iun 4935  df-br 5086  df-opab 5148  df-mpt 5167  df-tr 5193  df-id 5526  df-eprel 5531  df-po 5539  df-so 5540  df-fr 5584  df-se 5585  df-we 5586  df-xp 5637  df-rel 5638  df-cnv 5639  df-co 5640  df-dm 5641  df-rn 5642  df-res 5643  df-ima 5644  df-pred 6265  df-ord 6326  df-on 6327  df-lim 6328  df-suc 6329  df-iota 6454  df-fun 6500  df-fn 6501  df-f 6502  df-f1 6503  df-fo 6504  df-f1o 6505  df-fv 6506  df-riota 7324  df-ov 7370  df-oprab 7371  df-mpo 7372  df-om 7818  df-1st 7942  df-2nd 7943  df-frecs 8231  df-wrecs 8262  df-recs 8311  df-rdg 8349  df-1o 8405  df-2o 8406  df-oadd 8409  df-nadd 8602  df-no 27606  df-lts 27607  df-bday 27608  df-les 27709  df-slts 27750  df-cuts 27752  df-0s 27799  df-1s 27800  df-made 27819  df-old 27820  df-left 27822  df-right 27823  df-norec 27930  df-norec2 27941  df-adds 27952  df-negs 28013  df-subs 28014  df-muls 28099  df-divs 28180  df-abss 28230  df-n0s 28306  df-nns 28307  df-reno 28482

This theorem is referenced by: (None)