| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | mulscl 28161 | . . . . 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 28434 | . . . . . . 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 3212 | . . . . 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 613 | . . . . . 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 3228 | . . . . . 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 613 | . . . . 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 28429 | . . . . . . . . 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 28429 | . . . . . . . 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 727 | . . . . . . 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 770 | . . . . . . 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 772 | . . . . . . 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 28197 | . . . . . 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 3188 | . . . . . . . . . . . . . 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 1847 | . . . . . . . . . . . . 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 3287 | . . . . . . . . . . . . 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 3178 | . . . . . . . . . . . . . 14
⊢ (𝑥 = 𝑡 → (∃𝑛 ∈ ℕs 𝑥 = (𝐴 -s ( 1s
/su 𝑛))
↔ ∃𝑛 ∈
ℕs 𝑡 =
(𝐴 -s (
1s /su 𝑛)))) | 
| 28 | 27 | rexab 3699 | . . . . . . . . . . . . 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 7465 | . . . . . . . . . . . . . . . . 17
⊢ (𝐴 -s ( 1s
/su 𝑛))
∈ V | 
| 31 |  | oveq2 7440 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (𝑡 = (𝐴 -s ( 1s
/su 𝑛))
→ (𝐴 -s
𝑡) = (𝐴 -s (𝐴 -s ( 1s
/su 𝑛)))) | 
| 32 | 31 | oveq1d 7447 | . . . . . . . . . . . . . . . . . . . 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 7448 | . . . . . . . . . . . . . . . . . . 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 3178 | . . . . . . . . . . . . . . . . 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 3531 | . . . . . . . . . . . . . . . 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 3188 | . . . . . . . . . . . . . . . . . 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 1847 | . . . . . . . . . . . . . . . . 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 3287 | . . . . . . . . . . . . . . . . 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 3178 | . . . . . . . . . . . . . . . . . 18
⊢ (𝑦 = 𝑢 → (∃𝑚 ∈ ℕs 𝑦 = (𝐵 -s ( 1s
/su 𝑚))
↔ ∃𝑚 ∈
ℕs 𝑢 =
(𝐵 -s (
1s /su 𝑚)))) | 
| 42 | 41 | rexab 3699 | . . . . . . . . . . . . . . . . 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 7465 | . . . . . . . . . . . . . . . . . 18
⊢ (𝐵 -s ( 1s
/su 𝑚))
∈ V | 
| 46 |  | oveq2 7440 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (𝑢 = (𝐵 -s ( 1s
/su 𝑚))
→ (𝐵 -s
𝑢) = (𝐵 -s (𝐵 -s ( 1s
/su 𝑚)))) | 
| 47 | 46 | oveq2d 7448 | . . . . . . . . . . . . . . . . . . . 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 7448 | . . . . . . . . . . . . . . . . . . 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 3531 | . . . . . . . . . . . . . . . . 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 774 | . . . . . . . . . . . . . . . . . . . . 21
⊢ ((((𝐴 ∈ 
No  ∧ 𝐵 ∈
 No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs)
→ 𝐴 ∈  No ) | 
| 52 |  | 1sno 27873 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ 
1s ∈  No | 
| 53 | 52 | a1i 11 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ ((((𝐴 ∈ 
No  ∧ 𝐵 ∈
 No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs)
→ 1s ∈  No ) | 
| 54 |  | nnsno 28330 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ (𝑛 ∈ ℕs
→ 𝑛 ∈  No ) | 
| 55 | 54 | ad2antlr 727 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ ((((𝐴 ∈ 
No  ∧ 𝐵 ∈
 No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs)
→ 𝑛 ∈  No ) | 
| 56 |  | nnne0s 28341 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ (𝑛 ∈ ℕs
→ 𝑛 ≠ 0s
) | 
| 57 | 56 | ad2antlr 727 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ ((((𝐴 ∈ 
No  ∧ 𝐵 ∈
 No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs)
→ 𝑛 ≠ 0s
) | 
| 58 | 53, 55, 57 | divscld 28249 | . . . . . . . . . . . . . . . . . . . . 21
⊢ ((((𝐴 ∈ 
No  ∧ 𝐵 ∈
 No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs)
→ ( 1s /su 𝑛) ∈  No
) | 
| 59 | 51, 58 | nncansd 28127 | . . . . . . . . . . . . . . . . . . . 20
⊢ ((((𝐴 ∈ 
No  ∧ 𝐵 ∈
 No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs)
→ (𝐴 -s
(𝐴 -s (
1s /su 𝑛))) = ( 1s /su
𝑛)) | 
| 60 |  | simpllr 775 | . . . . . . . . . . . . . . . . . . . . 21
⊢ ((((𝐴 ∈ 
No  ∧ 𝐵 ∈
 No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs)
→ 𝐵 ∈  No ) | 
| 61 |  | nnsno 28330 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ (𝑚 ∈ ℕs
→ 𝑚 ∈  No ) | 
| 62 | 61 | adantl 481 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ ((((𝐴 ∈ 
No  ∧ 𝐵 ∈
 No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs)
→ 𝑚 ∈  No ) | 
| 63 |  | nnne0s 28341 | . . . . . . . . . . . . . . . . . . . . . . 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 28249 | . . . . . . . . . . . . . . . . . . . . 21
⊢ ((((𝐴 ∈ 
No  ∧ 𝐵 ∈
 No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs)
→ ( 1s /su 𝑚) ∈  No
) | 
| 66 | 60, 65 | nncansd 28127 | . . . . . . . . . . . . . . . . . . . 20
⊢ ((((𝐴 ∈ 
No  ∧ 𝐵 ∈
 No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs)
→ (𝐵 -s
(𝐵 -s (
1s /su 𝑚))) = ( 1s /su
𝑚)) | 
| 67 | 59, 66 | oveq12d 7450 | . . . . . . . . . . . . . . . . . . 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 7448 | . . . . . . . . . . . . . . . . . 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 3176 | . . . . . . . . . . . . . . 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 3176 | . . . . . . . . . . . . 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 28433 | . . . . . . . . . . . . 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 2807 | . . . . . . . . . 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 3188 | . . . . . . . . . . . . . 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 1847 | . . . . . . . . . . . . 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 3287 | . . . . . . . . . . . . 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 3178 | . . . . . . . . . . . . . 14
⊢ (𝑥 = 𝑡 → (∃𝑛 ∈ ℕs 𝑥 = (𝐴 +s ( 1s
/su 𝑛))
↔ ∃𝑛 ∈
ℕs 𝑡 =
(𝐴 +s (
1s /su 𝑛)))) | 
| 83 | 82 | rexab 3699 | . . . . . . . . . . . . 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 7465 | . . . . . . . . . . . . . . . . 17
⊢ (𝐴 +s ( 1s
/su 𝑛))
∈ V | 
| 86 |  | oveq1 7439 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (𝑡 = (𝐴 +s ( 1s
/su 𝑛))
→ (𝑡 -s
𝐴) = ((𝐴 +s ( 1s
/su 𝑛))
-s 𝐴)) | 
| 87 | 86 | oveq1d 7447 | . . . . . . . . . . . . . . . . . . . 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 7448 | . . . . . . . . . . . . . . . . . . 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 3178 | . . . . . . . . . . . . . . . . 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 3531 | . . . . . . . . . . . . . . . 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 3188 | . . . . . . . . . . . . . . . . . 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 1847 | . . . . . . . . . . . . . . . . 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 3287 | . . . . . . . . . . . . . . . . 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 3178 | . . . . . . . . . . . . . . . . . 18
⊢ (𝑦 = 𝑢 → (∃𝑚 ∈ ℕs 𝑦 = (𝐵 +s ( 1s
/su 𝑚))
↔ ∃𝑚 ∈
ℕs 𝑢 =
(𝐵 +s (
1s /su 𝑚)))) | 
| 97 | 96 | rexab 3699 | . . . . . . . . . . . . . . . . 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 7465 | . . . . . . . . . . . . . . . . . 18
⊢ (𝐵 +s ( 1s
/su 𝑚))
∈ V | 
| 101 |  | oveq1 7439 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (𝑢 = (𝐵 +s ( 1s
/su 𝑚))
→ (𝑢 -s
𝐵) = ((𝐵 +s ( 1s
/su 𝑚))
-s 𝐵)) | 
| 102 | 101 | oveq2d 7448 | . . . . . . . . . . . . . . . . . . . 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 7448 | . . . . . . . . . . . . . . . . . . 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 3531 | . . . . . . . . . . . . . . . . 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 28105 | . . . . . . . . . . . . . . . . . . . . 21
⊢ ((𝐴 ∈ 
No  ∧ ( 1s /su 𝑛) ∈  No )
→ ((𝐴 +s (
1s /su 𝑛)) -s 𝐴) = ( 1s /su 𝑛)) | 
| 107 | 51, 58, 106 | syl2anc 584 | . . . . . . . . . . . . . . . . . . . 20
⊢ ((((𝐴 ∈ 
No  ∧ 𝐵 ∈
 No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs)
→ ((𝐴 +s (
1s /su 𝑛)) -s 𝐴) = ( 1s /su 𝑛)) | 
| 108 |  | pncan2s 28105 | . . . . . . . . . . . . . . . . . . . . 21
⊢ ((𝐵 ∈ 
No  ∧ ( 1s /su 𝑚) ∈  No )
→ ((𝐵 +s (
1s /su 𝑚)) -s 𝐵) = ( 1s /su 𝑚)) | 
| 109 | 60, 65, 108 | syl2anc 584 | . . . . . . . . . . . . . . . . . . . 20
⊢ ((((𝐴 ∈ 
No  ∧ 𝐵 ∈
 No ) ∧ 𝑛 ∈ ℕs) ∧ 𝑚 ∈ ℕs)
→ ((𝐵 +s (
1s /su 𝑚)) -s 𝐵) = ( 1s /su 𝑚)) | 
| 110 | 107, 109 | oveq12d 7450 | . . . . . . . . . . . . . . . . . . 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 7448 | . . . . . . . . . . . . . . . . . 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 3176 | . . . . . . . . . . . . . . 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 3176 | . . . . . . . . . . . . 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 2807 | . . . . . . . . . 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 4168 | . . . . . . . . 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 4156 | . . . . . . . . 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 2792 | . . . . . . . 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 3188 | . . . . . . . . . . . . . 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 1847 | . . . . . . . . . . . . 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 3287 | . . . . . . . . . . . . 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 3699 | . . . . . . . . . . . . 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 7447 | . . . . . . . . . . . . . . . . . . . 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 7448 | . . . . . . . . . . . . . . . . . . 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 3178 | . . . . . . . . . . . . . . . . 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 3531 | . . . . . . . . . . . . . . . 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 3188 | . . . . . . . . . . . . . . . . . 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 1847 | . . . . . . . . . . . . . . . . 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 3287 | . . . . . . . . . . . . . . . . 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 3699 | . . . . . . . . . . . . . . . . 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 7448 | . . . . . . . . . . . . . . . . . . . 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 7448 | . . . . . . . . . . . . . . . . . . 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 3531 | . . . . . . . . . . . . . . . . 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 7450 | . . . . . . . . . . . . . . . . . . 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 7448 | . . . . . . . . . . . . . . . . . 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 3176 | . . . . . . . . . . . . . . 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 3176 | . . . . . . . . . . . . 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 28433 | . . . . . . . . . . . . 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 2807 | . . . . . . . . . 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 3188 | . . . . . . . . . . . . . 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 1847 | . . . . . . . . . . . . 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 3287 | . . . . . . . . . . . . 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 3699 | . . . . . . . . . . . . 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 7447 | . . . . . . . . . . . . . . . . . . . 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 7448 | . . . . . . . . . . . . . . . . . . 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 3178 | . . . . . . . . . . . . . . . . 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 3531 | . . . . . . . . . . . . . . . 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 3188 | . . . . . . . . . . . . . . . . . 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 1847 | . . . . . . . . . . . . . . . . 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 3287 | . . . . . . . . . . . . . . . . 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 3699 | . . . . . . . . . . . . . . . . 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 7448 | . . . . . . . . . . . . . . . . . . . 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 7448 | . . . . . . . . . . . . . . . . . . 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 3531 | . . . . . . . . . . . . . . . . 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 7450 | . . . . . . . . . . . . . . . . . . 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 7448 | . . . . . . . . . . . . . . . . . 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 3176 | . . . . . . . . . . . . . . 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 3176 | . . . . . . . . . . . . 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 2807 | . . . . . . . . . 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 4168 | . . . . . . . . 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 4156 | . . . . . . . . 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 2792 | . . . . . . . 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 7450 | . . . . . . 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 2776 | . . . . 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 593 | . . . 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 660 | . 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 28428 | . . 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 28428 | . . 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 628 | . 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 28428 | . 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) |