xmulasslem3 - Metamath Proof Explorer

	Metamath Proof Explorer		< Previous Next > Nearby theorems
Mirrors > Home > MPE Home > Th. List > xmulasslem3		Structured version Visualization version GIF version

Theorem xmulasslem3 12673

Description: Lemma for xmulass 12674. (Contributed by Mario Carneiro, 20-Aug-2015.)

**Assertion**
Ref	Expression
xmulasslem3	⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))

**Proof of Theorem xmulasslem3**
Step	Hyp	Ref	Expression
1		recn 10621	. . . . . . . . . 10 ⊢ (𝐴 ∈ ℝ → 𝐴 ∈ ℂ)
2		recn 10621	. . . . . . . . . 10 ⊢ (𝐵 ∈ ℝ → 𝐵 ∈ ℂ)
3		recn 10621	. . . . . . . . . 10 ⊢ (𝐶 ∈ ℝ → 𝐶 ∈ ℂ)
4		mulass 10619	. . . . . . . . . 10 ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ∧ 𝐶 ∈ ℂ) → ((𝐴 · 𝐵) · 𝐶) = (𝐴 · (𝐵 · 𝐶)))
5	1, 2, 3, 4	syl3an 1156	. . . . . . . . 9 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → ((𝐴 · 𝐵) · 𝐶) = (𝐴 · (𝐵 · 𝐶)))
6	5	3expa 1114	. . . . . . . 8 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝐶 ∈ ℝ) → ((𝐴 · 𝐵) · 𝐶) = (𝐴 · (𝐵 · 𝐶)))
7		remulcl 10616	. . . . . . . . 9 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 · 𝐵) ∈ ℝ)
8		rexmul 12658	. . . . . . . . 9 ⊢ (((𝐴 · 𝐵) ∈ ℝ ∧ 𝐶 ∈ ℝ) → ((𝐴 · 𝐵) ·_e 𝐶) = ((𝐴 · 𝐵) · 𝐶))
9	7, 8	sylan 582	. . . . . . . 8 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝐶 ∈ ℝ) → ((𝐴 · 𝐵) ·_e 𝐶) = ((𝐴 · 𝐵) · 𝐶))
10		remulcl 10616	. . . . . . . . . 10 ⊢ ((𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → (𝐵 · 𝐶) ∈ ℝ)
11		rexmul 12658	. . . . . . . . . 10 ⊢ ((𝐴 ∈ ℝ ∧ (𝐵 · 𝐶) ∈ ℝ) → (𝐴 ·_e (𝐵 · 𝐶)) = (𝐴 · (𝐵 · 𝐶)))
12	10, 11	sylan2 594	. . . . . . . . 9 ⊢ ((𝐴 ∈ ℝ ∧ (𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ)) → (𝐴 ·_e (𝐵 · 𝐶)) = (𝐴 · (𝐵 · 𝐶)))
13	12	anassrs 470	. . . . . . . 8 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝐶 ∈ ℝ) → (𝐴 ·_e (𝐵 · 𝐶)) = (𝐴 · (𝐵 · 𝐶)))
14	6, 9, 13	3eqtr4d 2866	. . . . . . 7 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝐶 ∈ ℝ) → ((𝐴 · 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 · 𝐶)))
15		rexmul 12658	. . . . . . . . 9 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 ·_e 𝐵) = (𝐴 · 𝐵))
16	15	adantr 483	. . . . . . . 8 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝐶 ∈ ℝ) → (𝐴 ·_e 𝐵) = (𝐴 · 𝐵))
17	16	oveq1d 7165	. . . . . . 7 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝐶 ∈ ℝ) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = ((𝐴 · 𝐵) ·_e 𝐶))
18		rexmul 12658	. . . . . . . . 9 ⊢ ((𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → (𝐵 ·_e 𝐶) = (𝐵 · 𝐶))
19	18	adantll 712	. . . . . . . 8 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝐶 ∈ ℝ) → (𝐵 ·_e 𝐶) = (𝐵 · 𝐶))
20	19	oveq2d 7166	. . . . . . 7 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝐶 ∈ ℝ) → (𝐴 ·_e (𝐵 ·_e 𝐶)) = (𝐴 ·_e (𝐵 · 𝐶)))
21	14, 17, 20	3eqtr4d 2866	. . . . . 6 ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝐶 ∈ ℝ) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))
22	21	adantll 712	. . . . 5 ⊢ (((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ (𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ)) ∧ 𝐶 ∈ ℝ) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))
23		oveq2 7158	. . . . . . . . 9 ⊢ (𝐶 = +∞ → ((𝐴 ·_e 𝐵) ·_e 𝐶) = ((𝐴 ·_e 𝐵) ·_e +∞))
24		simp1l 1193	. . . . . . . . . . 11 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → 𝐴 ∈ ℝ^*)
25		simp2l 1195	. . . . . . . . . . 11 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → 𝐵 ∈ ℝ^*)
26		xmulcl 12660	. . . . . . . . . . 11 ⊢ ((𝐴 ∈ ℝ^* ∧ 𝐵 ∈ ℝ^) → (𝐴 ·_e 𝐵) ∈ ℝ^)
27	24, 25, 26	syl2anc 586	. . . . . . . . . 10 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → (𝐴 ·_e 𝐵) ∈ ℝ^*)
28		xmulgt0 12670	. . . . . . . . . . 11 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵)) → 0 < (𝐴 ·_e 𝐵))
29	28	3adant3 1128	. . . . . . . . . 10 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → 0 < (𝐴 ·_e 𝐵))
30		xmulpnf1 12661	. . . . . . . . . 10 ⊢ (((𝐴 ·_e 𝐵) ∈ ℝ^* ∧ 0 < (𝐴 ·_e 𝐵)) → ((𝐴 ·_e 𝐵) ·_e +∞) = +∞)
31	27, 29, 30	syl2anc 586	. . . . . . . . 9 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → ((𝐴 ·_e 𝐵) ·_e +∞) = +∞)
32	23, 31	sylan9eqr 2878	. . . . . . . 8 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐶 = +∞) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = +∞)
33		simpl1 1187	. . . . . . . . 9 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐶 = +∞) → (𝐴 ∈ ℝ^* ∧ 0 < 𝐴))
34		xmulpnf1 12661	. . . . . . . . 9 ⊢ ((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) → (𝐴 ·_e +∞) = +∞)
35	33, 34	syl 17	. . . . . . . 8 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐶 = +∞) → (𝐴 ·_e +∞) = +∞)
36	32, 35	eqtr4d 2859	. . . . . . 7 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐶 = +∞) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e +∞))
37		oveq2 7158	. . . . . . . . 9 ⊢ (𝐶 = +∞ → (𝐵 ·_e 𝐶) = (𝐵 ·_e +∞))
38		xmulpnf1 12661	. . . . . . . . . 10 ⊢ ((𝐵 ∈ ℝ^* ∧ 0 < 𝐵) → (𝐵 ·_e +∞) = +∞)
39	38	3ad2ant2 1130	. . . . . . . . 9 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → (𝐵 ·_e +∞) = +∞)
40	37, 39	sylan9eqr 2878	. . . . . . . 8 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐶 = +∞) → (𝐵 ·_e 𝐶) = +∞)
41	40	oveq2d 7166	. . . . . . 7 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐶 = +∞) → (𝐴 ·_e (𝐵 ·_e 𝐶)) = (𝐴 ·_e +∞))
42	36, 41	eqtr4d 2859	. . . . . 6 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐶 = +∞) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))
43	42	adantlr 713	. . . . 5 ⊢ (((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ (𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ)) ∧ 𝐶 = +∞) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))
44		simpl3r 1225	. . . . . 6 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ (𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ)) → 0 < 𝐶)
45		xmulasslem2 12669	. . . . . 6 ⊢ ((0 < 𝐶 ∧ 𝐶 = -∞) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))
46	44, 45	sylan 582	. . . . 5 ⊢ (((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ (𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ)) ∧ 𝐶 = -∞) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))
47		simp3l 1197	. . . . . . 7 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → 𝐶 ∈ ℝ^*)
48		elxr 12505	. . . . . . 7 ⊢ (𝐶 ∈ ℝ^* ↔ (𝐶 ∈ ℝ ∨ 𝐶 = +∞ ∨ 𝐶 = -∞))
49	47, 48	sylib 220	. . . . . 6 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → (𝐶 ∈ ℝ ∨ 𝐶 = +∞ ∨ 𝐶 = -∞))
50	49	adantr 483	. . . . 5 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ (𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ)) → (𝐶 ∈ ℝ ∨ 𝐶 = +∞ ∨ 𝐶 = -∞))
51	22, 43, 46, 50	mpjao3dan 1427	. . . 4 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ (𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ)) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))
52	51	anassrs 470	. . 3 ⊢ (((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐴 ∈ ℝ) ∧ 𝐵 ∈ ℝ) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))
53		xmulpnf2 12662	. . . . . . . 8 ⊢ ((𝐶 ∈ ℝ^* ∧ 0 < 𝐶) → (+∞ ·_e 𝐶) = +∞)
54	53	3ad2ant3 1131	. . . . . . 7 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → (+∞ ·_e 𝐶) = +∞)
55	34	3ad2ant1 1129	. . . . . . 7 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → (𝐴 ·_e +∞) = +∞)
56	54, 55	eqtr4d 2859	. . . . . 6 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → (+∞ ·_e 𝐶) = (𝐴 ·_e +∞))
57	56	adantr 483	. . . . 5 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐵 = +∞) → (+∞ ·_e 𝐶) = (𝐴 ·_e +∞))
58		oveq2 7158	. . . . . . 7 ⊢ (𝐵 = +∞ → (𝐴 ·_e 𝐵) = (𝐴 ·_e +∞))
59	58, 55	sylan9eqr 2878	. . . . . 6 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐵 = +∞) → (𝐴 ·_e 𝐵) = +∞)
60	59	oveq1d 7165	. . . . 5 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐵 = +∞) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (+∞ ·_e 𝐶))
61		oveq1 7157	. . . . . . 7 ⊢ (𝐵 = +∞ → (𝐵 ·_e 𝐶) = (+∞ ·_e 𝐶))
62	61, 54	sylan9eqr 2878	. . . . . 6 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐵 = +∞) → (𝐵 ·_e 𝐶) = +∞)
63	62	oveq2d 7166	. . . . 5 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐵 = +∞) → (𝐴 ·_e (𝐵 ·_e 𝐶)) = (𝐴 ·_e +∞))
64	57, 60, 63	3eqtr4d 2866	. . . 4 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐵 = +∞) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))
65	64	adantlr 713	. . 3 ⊢ (((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐴 ∈ ℝ) ∧ 𝐵 = +∞) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))
66		simpl2r 1223	. . . 4 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐴 ∈ ℝ) → 0 < 𝐵)
67		xmulasslem2 12669	. . . 4 ⊢ ((0 < 𝐵 ∧ 𝐵 = -∞) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))
68	66, 67	sylan 582	. . 3 ⊢ (((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐴 ∈ ℝ) ∧ 𝐵 = -∞) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))
69		elxr 12505	. . . . 5 ⊢ (𝐵 ∈ ℝ^* ↔ (𝐵 ∈ ℝ ∨ 𝐵 = +∞ ∨ 𝐵 = -∞))
70	25, 69	sylib 220	. . . 4 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → (𝐵 ∈ ℝ ∨ 𝐵 = +∞ ∨ 𝐵 = -∞))
71	70	adantr 483	. . 3 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐴 ∈ ℝ) → (𝐵 ∈ ℝ ∨ 𝐵 = +∞ ∨ 𝐵 = -∞))
72	52, 65, 68, 71	mpjao3dan 1427	. 2 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐴 ∈ ℝ) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))
73		simpl3 1189	. . . 4 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐴 = +∞) → (𝐶 ∈ ℝ^* ∧ 0 < 𝐶))
74	73, 53	syl 17	. . 3 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐴 = +∞) → (+∞ ·_e 𝐶) = +∞)
75		oveq1 7157	. . . . 5 ⊢ (𝐴 = +∞ → (𝐴 ·_e 𝐵) = (+∞ ·_e 𝐵))
76		xmulpnf2 12662	. . . . . 6 ⊢ ((𝐵 ∈ ℝ^* ∧ 0 < 𝐵) → (+∞ ·_e 𝐵) = +∞)
77	76	3ad2ant2 1130	. . . . 5 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → (+∞ ·_e 𝐵) = +∞)
78	75, 77	sylan9eqr 2878	. . . 4 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐴 = +∞) → (𝐴 ·_e 𝐵) = +∞)
79	78	oveq1d 7165	. . 3 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐴 = +∞) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (+∞ ·_e 𝐶))
80		oveq1 7157	. . . 4 ⊢ (𝐴 = +∞ → (𝐴 ·_e (𝐵 ·_e 𝐶)) = (+∞ ·_e (𝐵 ·_e 𝐶)))
81		xmulcl 12660	. . . . . 6 ⊢ ((𝐵 ∈ ℝ^* ∧ 𝐶 ∈ ℝ^) → (𝐵 ·_e 𝐶) ∈ ℝ^)
82	25, 47, 81	syl2anc 586	. . . . 5 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → (𝐵 ·_e 𝐶) ∈ ℝ^*)
83		xmulgt0 12670	. . . . . 6 ⊢ (((𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → 0 < (𝐵 ·_e 𝐶))
84	83	3adant1 1126	. . . . 5 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → 0 < (𝐵 ·_e 𝐶))
85		xmulpnf2 12662	. . . . 5 ⊢ (((𝐵 ·_e 𝐶) ∈ ℝ^* ∧ 0 < (𝐵 ·_e 𝐶)) → (+∞ ·_e (𝐵 ·_e 𝐶)) = +∞)
86	82, 84, 85	syl2anc 586	. . . 4 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → (+∞ ·_e (𝐵 ·_e 𝐶)) = +∞)
87	80, 86	sylan9eqr 2878	. . 3 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐴 = +∞) → (𝐴 ·_e (𝐵 ·_e 𝐶)) = +∞)
88	74, 79, 87	3eqtr4d 2866	. 2 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐴 = +∞) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))
89		simp1r 1194	. . 3 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → 0 < 𝐴)
90		xmulasslem2 12669	. . 3 ⊢ ((0 < 𝐴 ∧ 𝐴 = -∞) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))
91	89, 90	sylan 582	. 2 ⊢ ((((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) ∧ 𝐴 = -∞) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))
92		elxr 12505	. . 3 ⊢ (𝐴 ∈ ℝ^* ↔ (𝐴 ∈ ℝ ∨ 𝐴 = +∞ ∨ 𝐴 = -∞))
93	24, 92	sylib 220	. 2 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → (𝐴 ∈ ℝ ∨ 𝐴 = +∞ ∨ 𝐴 = -∞))
94	72, 88, 91, 93	mpjao3dan 1427	1 ⊢ (((𝐴 ∈ ℝ^* ∧ 0 < 𝐴) ∧ (𝐵 ∈ ℝ^* ∧ 0 < 𝐵) ∧ (𝐶 ∈ ℝ^* ∧ 0 < 𝐶)) → ((𝐴 ·_e 𝐵) ·_e 𝐶) = (𝐴 ·_e (𝐵 ·_e 𝐶)))

Colors of variables: wff setvar class

Syntax hints: → wi 4 ∧ wa 398 ∨ w3o 1082 ∧ w3a 1083 = wceq 1533 ∈ wcel 2110 class class class wbr 5058 (class class class)co 7150 ℂcc 10529 ℝcr 10530 0cc0 10531 · cmul 10536 +∞cpnf 10666 -∞cmnf 10667 ℝ^*cxr 10668 < clt 10669 ·_e cxmu 12500

This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1792 ax-4 1806 ax-5 1907 ax-6 1966 ax-7 2011 ax-8 2112 ax-9 2120 ax-10 2141 ax-11 2157 ax-12 2173 ax-ext 2793 ax-sep 5195 ax-nul 5202 ax-pow 5258 ax-pr 5321 ax-un 7455 ax-cnex 10587 ax-resscn 10588 ax-1cn 10589 ax-icn 10590 ax-addcl 10591 ax-addrcl 10592 ax-mulcl 10593 ax-mulrcl 10594 ax-mulcom 10595 ax-addass 10596 ax-mulass 10597 ax-distr 10598 ax-i2m1 10599 ax-1ne0 10600 ax-1rid 10601 ax-rnegex 10602 ax-rrecex 10603 ax-cnre 10604 ax-pre-lttri 10605 ax-pre-lttrn 10606 ax-pre-ltadd 10607 ax-pre-mulgt0 10608

This theorem depends on definitions: df-bi 209 df-an 399 df-or 844 df-3or 1084 df-3an 1085 df-tru 1536 df-ex 1777 df-nf 1781 df-sb 2066 df-mo 2618 df-eu 2650 df-clab 2800 df-cleq 2814 df-clel 2893 df-nfc 2963 df-ne 3017 df-nel 3124 df-ral 3143 df-rex 3144 df-rab 3147 df-v 3496 df-sbc 3772 df-csb 3883 df-dif 3938 df-un 3940 df-in 3942 df-ss 3951 df-nul 4291 df-if 4467 df-pw 4540 df-sn 4561 df-pr 4563 df-op 4567 df-uni 4832 df-iun 4913 df-br 5059 df-opab 5121 df-mpt 5139 df-id 5454 df-po 5468 df-so 5469 df-xp 5555 df-rel 5556 df-cnv 5557 df-co 5558 df-dm 5559 df-rn 5560 df-res 5561 df-ima 5562 df-iota 6308 df-fun 6351 df-fn 6352 df-f 6353 df-f1 6354 df-fo 6355 df-f1o 6356 df-fv 6357 df-ov 7153 df-oprab 7154 df-mpo 7155 df-1st 7683 df-2nd 7684 df-er 8283 df-en 8504 df-dom 8505 df-sdom 8506 df-pnf 10671 df-mnf 10672 df-xr 10673 df-ltxr 10674 df-xmul 12503

This theorem is referenced by: xmulass 12674

W3C validator