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Theorem ptolemy 14248

Description: Ptolemy's Theorem. This theorem is named after the Greek astronomer and mathematician Ptolemy (Claudius Ptolemaeus). This particular version is expressed using the sine function. It is proved by expanding all the multiplication of sines to a product of cosines of differences using sinmul 11752, then using algebraic simplification to show that both sides are equal. This formalization is based on the proof in "Trigonometry" by Gelfand and Saul. This is Metamath 100 proof #95. (Contributed by David A. Wheeler, 31-May-2015.)

**Assertion**
Ref	Expression
ptolemy	⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (((sin‘𝐴) · (sin‘𝐵)) + ((sin‘𝐶) · (sin‘𝐷))) = ((sin‘(𝐵 + 𝐶)) · (sin‘(𝐴 + 𝐶))))

**Proof of Theorem ptolemy**
Step	Hyp	Ref	Expression
1		addcl 7936	. . . . . . . . . . 11 ⊢ ((𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) → (𝐶 + 𝐷) ∈ ℂ)
2	1	3ad2ant2 1019	. . . . . . . . . 10 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (𝐶 + 𝐷) ∈ ℂ)
3	2	coscld 11719	. . . . . . . . 9 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (cos‘(𝐶 + 𝐷)) ∈ ℂ)
4	3	negnegd 8259	. . . . . . . 8 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → --(cos‘(𝐶 + 𝐷)) = (cos‘(𝐶 + 𝐷)))
5		addlid 8096	. . . . . . . . . . . . . . 15 ⊢ ((𝐶 + 𝐷) ∈ ℂ → (0 + (𝐶 + 𝐷)) = (𝐶 + 𝐷))
6	5	oveq1d 5890	. . . . . . . . . . . . . 14 ⊢ ((𝐶 + 𝐷) ∈ ℂ → ((0 + (𝐶 + 𝐷)) − ((𝐴 + 𝐵) + (𝐶 + 𝐷))) = ((𝐶 + 𝐷) − ((𝐴 + 𝐵) + (𝐶 + 𝐷))))
7	2, 6	syl 14	. . . . . . . . . . . . 13 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((0 + (𝐶 + 𝐷)) − ((𝐴 + 𝐵) + (𝐶 + 𝐷))) = ((𝐶 + 𝐷) − ((𝐴 + 𝐵) + (𝐶 + 𝐷))))
8		0cnd 7950	. . . . . . . . . . . . . 14 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → 0 ∈ ℂ)
9		addcl 7936	. . . . . . . . . . . . . . . 16 ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) → (𝐴 + 𝐵) ∈ ℂ)
10	9	adantr 276	. . . . . . . . . . . . . . 15 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → (𝐴 + 𝐵) ∈ ℂ)
11	10	3adant3 1017	. . . . . . . . . . . . . 14 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (𝐴 + 𝐵) ∈ ℂ)
12	8, 11, 2	pnpcan2d 8306	. . . . . . . . . . . . 13 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((0 + (𝐶 + 𝐷)) − ((𝐴 + 𝐵) + (𝐶 + 𝐷))) = (0 − (𝐴 + 𝐵)))
13		simp3 999	. . . . . . . . . . . . . 14 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π)
14	13	oveq2d 5891	. . . . . . . . . . . . 13 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((𝐶 + 𝐷) − ((𝐴 + 𝐵) + (𝐶 + 𝐷))) = ((𝐶 + 𝐷) − π))
15	7, 12, 14	3eqtr3rd 2219	. . . . . . . . . . . 12 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((𝐶 + 𝐷) − π) = (0 − (𝐴 + 𝐵)))
16		df-neg 8131	. . . . . . . . . . . 12 ⊢ -(𝐴 + 𝐵) = (0 − (𝐴 + 𝐵))
17	15, 16	eqtr4di 2228	. . . . . . . . . . 11 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((𝐶 + 𝐷) − π) = -(𝐴 + 𝐵))
18	17	fveq2d 5520	. . . . . . . . . 10 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (cos‘((𝐶 + 𝐷) − π)) = (cos‘-(𝐴 + 𝐵)))
19		cosmpi 14240	. . . . . . . . . . 11 ⊢ ((𝐶 + 𝐷) ∈ ℂ → (cos‘((𝐶 + 𝐷) − π)) = -(cos‘(𝐶 + 𝐷)))
20	2, 19	syl 14	. . . . . . . . . 10 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (cos‘((𝐶 + 𝐷) − π)) = -(cos‘(𝐶 + 𝐷)))
21		cosneg 11735	. . . . . . . . . . 11 ⊢ ((𝐴 + 𝐵) ∈ ℂ → (cos‘-(𝐴 + 𝐵)) = (cos‘(𝐴 + 𝐵)))
22	11, 21	syl 14	. . . . . . . . . 10 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (cos‘-(𝐴 + 𝐵)) = (cos‘(𝐴 + 𝐵)))
23	18, 20, 22	3eqtr3d 2218	. . . . . . . . 9 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → -(cos‘(𝐶 + 𝐷)) = (cos‘(𝐴 + 𝐵)))
24	23	negeqd 8152	. . . . . . . 8 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → --(cos‘(𝐶 + 𝐷)) = -(cos‘(𝐴 + 𝐵)))
25	4, 24	eqtr3d 2212	. . . . . . 7 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (cos‘(𝐶 + 𝐷)) = -(cos‘(𝐴 + 𝐵)))
26	25	oveq2d 5891	. . . . . 6 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((cos‘(𝐶 − 𝐷)) − (cos‘(𝐶 + 𝐷))) = ((cos‘(𝐶 − 𝐷)) − -(cos‘(𝐴 + 𝐵))))
27		subcl 8156	. . . . . . . . . 10 ⊢ ((𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) → (𝐶 − 𝐷) ∈ ℂ)
28	27	adantl 277	. . . . . . . . 9 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → (𝐶 − 𝐷) ∈ ℂ)
29	28	coscld 11719	. . . . . . . 8 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → (cos‘(𝐶 − 𝐷)) ∈ ℂ)
30	29	3adant3 1017	. . . . . . 7 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (cos‘(𝐶 − 𝐷)) ∈ ℂ)
31	11	coscld 11719	. . . . . . 7 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (cos‘(𝐴 + 𝐵)) ∈ ℂ)
32	30, 31	subnegd 8275	. . . . . 6 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((cos‘(𝐶 − 𝐷)) − -(cos‘(𝐴 + 𝐵))) = ((cos‘(𝐶 − 𝐷)) + (cos‘(𝐴 + 𝐵))))
33	26, 32	eqtrd 2210	. . . . 5 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((cos‘(𝐶 − 𝐷)) − (cos‘(𝐶 + 𝐷))) = ((cos‘(𝐶 − 𝐷)) + (cos‘(𝐴 + 𝐵))))
34	33	oveq1d 5890	. . . 4 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (((cos‘(𝐶 − 𝐷)) − (cos‘(𝐶 + 𝐷))) / 2) = (((cos‘(𝐶 − 𝐷)) + (cos‘(𝐴 + 𝐵))) / 2))
35	34	oveq2d 5891	. . 3 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((((cos‘(𝐴 − 𝐵)) − (cos‘(𝐴 + 𝐵))) / 2) + (((cos‘(𝐶 − 𝐷)) − (cos‘(𝐶 + 𝐷))) / 2)) = ((((cos‘(𝐴 − 𝐵)) − (cos‘(𝐴 + 𝐵))) / 2) + (((cos‘(𝐶 − 𝐷)) + (cos‘(𝐴 + 𝐵))) / 2)))
36		subcl 8156	. . . . . . . 8 ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) → (𝐴 − 𝐵) ∈ ℂ)
37	36	3ad2ant1 1018	. . . . . . 7 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (𝐴 − 𝐵) ∈ ℂ)
38	37	coscld 11719	. . . . . 6 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (cos‘(𝐴 − 𝐵)) ∈ ℂ)
39	38, 31	subcld 8268	. . . . 5 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((cos‘(𝐴 − 𝐵)) − (cos‘(𝐴 + 𝐵))) ∈ ℂ)
40	30, 31	addcld 7977	. . . . 5 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((cos‘(𝐶 − 𝐷)) + (cos‘(𝐴 + 𝐵))) ∈ ℂ)
41		2cn 8990	. . . . . . 7 ⊢ 2 ∈ ℂ
42		2ap0 9012	. . . . . . 7 ⊢ 2 # 0
43	41, 42	pm3.2i 272	. . . . . 6 ⊢ (2 ∈ ℂ ∧ 2 # 0)
44	43	a1i 9	. . . . 5 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (2 ∈ ℂ ∧ 2 # 0))
45		divdirap 8654	. . . . 5 ⊢ ((((cos‘(𝐴 − 𝐵)) − (cos‘(𝐴 + 𝐵))) ∈ ℂ ∧ ((cos‘(𝐶 − 𝐷)) + (cos‘(𝐴 + 𝐵))) ∈ ℂ ∧ (2 ∈ ℂ ∧ 2 # 0)) → ((((cos‘(𝐴 − 𝐵)) − (cos‘(𝐴 + 𝐵))) + ((cos‘(𝐶 − 𝐷)) + (cos‘(𝐴 + 𝐵)))) / 2) = ((((cos‘(𝐴 − 𝐵)) − (cos‘(𝐴 + 𝐵))) / 2) + (((cos‘(𝐶 − 𝐷)) + (cos‘(𝐴 + 𝐵))) / 2)))
46	39, 40, 44, 45	syl3anc 1238	. . . 4 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((((cos‘(𝐴 − 𝐵)) − (cos‘(𝐴 + 𝐵))) + ((cos‘(𝐶 − 𝐷)) + (cos‘(𝐴 + 𝐵)))) / 2) = ((((cos‘(𝐴 − 𝐵)) − (cos‘(𝐴 + 𝐵))) / 2) + (((cos‘(𝐶 − 𝐷)) + (cos‘(𝐴 + 𝐵))) / 2)))
47	38, 31, 30	nppcan3d 8295	. . . . 5 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (((cos‘(𝐴 − 𝐵)) − (cos‘(𝐴 + 𝐵))) + ((cos‘(𝐶 − 𝐷)) + (cos‘(𝐴 + 𝐵)))) = ((cos‘(𝐴 − 𝐵)) + (cos‘(𝐶 − 𝐷))))
48	47	oveq1d 5890	. . . 4 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((((cos‘(𝐴 − 𝐵)) − (cos‘(𝐴 + 𝐵))) + ((cos‘(𝐶 − 𝐷)) + (cos‘(𝐴 + 𝐵)))) / 2) = (((cos‘(𝐴 − 𝐵)) + (cos‘(𝐶 − 𝐷))) / 2))
49	46, 48	eqtr3d 2212	. . 3 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((((cos‘(𝐴 − 𝐵)) − (cos‘(𝐴 + 𝐵))) / 2) + (((cos‘(𝐶 − 𝐷)) + (cos‘(𝐴 + 𝐵))) / 2)) = (((cos‘(𝐴 − 𝐵)) + (cos‘(𝐶 − 𝐷))) / 2))
50	35, 49	eqtrd 2210	. 2 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((((cos‘(𝐴 − 𝐵)) − (cos‘(𝐴 + 𝐵))) / 2) + (((cos‘(𝐶 − 𝐷)) − (cos‘(𝐶 + 𝐷))) / 2)) = (((cos‘(𝐴 − 𝐵)) + (cos‘(𝐶 − 𝐷))) / 2))
51		sinmul 11752	. . . 4 ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) → ((sin‘𝐴) · (sin‘𝐵)) = (((cos‘(𝐴 − 𝐵)) − (cos‘(𝐴 + 𝐵))) / 2))
52	51	3ad2ant1 1018	. . 3 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((sin‘𝐴) · (sin‘𝐵)) = (((cos‘(𝐴 − 𝐵)) − (cos‘(𝐴 + 𝐵))) / 2))
53		sinmul 11752	. . . 4 ⊢ ((𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) → ((sin‘𝐶) · (sin‘𝐷)) = (((cos‘(𝐶 − 𝐷)) − (cos‘(𝐶 + 𝐷))) / 2))
54	53	3ad2ant2 1019	. . 3 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((sin‘𝐶) · (sin‘𝐷)) = (((cos‘(𝐶 − 𝐷)) − (cos‘(𝐶 + 𝐷))) / 2))
55	52, 54	oveq12d 5893	. 2 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (((sin‘𝐴) · (sin‘𝐵)) + ((sin‘𝐶) · (sin‘𝐷))) = ((((cos‘(𝐴 − 𝐵)) − (cos‘(𝐴 + 𝐵))) / 2) + (((cos‘(𝐶 − 𝐷)) − (cos‘(𝐶 + 𝐷))) / 2)))
56		simplr 528	. . . . . . . . 9 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → 𝐵 ∈ ℂ)
57		simpll 527	. . . . . . . . 9 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → 𝐴 ∈ ℂ)
58		simprl 529	. . . . . . . . 9 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → 𝐶 ∈ ℂ)
59	56, 57, 58	pnpcan2d 8306	. . . . . . . 8 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → ((𝐵 + 𝐶) − (𝐴 + 𝐶)) = (𝐵 − 𝐴))
60	59	fveq2d 5520	. . . . . . 7 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → (cos‘((𝐵 + 𝐶) − (𝐴 + 𝐶))) = (cos‘(𝐵 − 𝐴)))
61	60	3adant3 1017	. . . . . 6 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (cos‘((𝐵 + 𝐶) − (𝐴 + 𝐶))) = (cos‘(𝐵 − 𝐴)))
62	1	adantl 277	. . . . . . . . . . . . 13 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → (𝐶 + 𝐷) ∈ ℂ)
63	10, 62, 28	3jca 1177	. . . . . . . . . . . 12 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → ((𝐴 + 𝐵) ∈ ℂ ∧ (𝐶 + 𝐷) ∈ ℂ ∧ (𝐶 − 𝐷) ∈ ℂ))
64	63	3adant3 1017	. . . . . . . . . . 11 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((𝐴 + 𝐵) ∈ ℂ ∧ (𝐶 + 𝐷) ∈ ℂ ∧ (𝐶 − 𝐷) ∈ ℂ))
65		addass 7941	. . . . . . . . . . 11 ⊢ (((𝐴 + 𝐵) ∈ ℂ ∧ (𝐶 + 𝐷) ∈ ℂ ∧ (𝐶 − 𝐷) ∈ ℂ) → (((𝐴 + 𝐵) + (𝐶 + 𝐷)) + (𝐶 − 𝐷)) = ((𝐴 + 𝐵) + ((𝐶 + 𝐷) + (𝐶 − 𝐷))))
66	64, 65	syl 14	. . . . . . . . . 10 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (((𝐴 + 𝐵) + (𝐶 + 𝐷)) + (𝐶 − 𝐷)) = ((𝐴 + 𝐵) + ((𝐶 + 𝐷) + (𝐶 − 𝐷))))
67		oveq1 5882	. . . . . . . . . . 11 ⊢ (((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π → (((𝐴 + 𝐵) + (𝐶 + 𝐷)) + (𝐶 − 𝐷)) = (π + (𝐶 − 𝐷)))
68	67	3ad2ant3 1020	. . . . . . . . . 10 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (((𝐴 + 𝐵) + (𝐶 + 𝐷)) + (𝐶 − 𝐷)) = (π + (𝐶 − 𝐷)))
69		simpl 109	. . . . . . . . . . . . . 14 ⊢ ((𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) → 𝐶 ∈ ℂ)
70		simpr 110	. . . . . . . . . . . . . 14 ⊢ ((𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) → 𝐷 ∈ ℂ)
71	69, 70, 69	3jca 1177	. . . . . . . . . . . . 13 ⊢ ((𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) → (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ ∧ 𝐶 ∈ ℂ))
72	71	3ad2ant2 1019	. . . . . . . . . . . 12 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ ∧ 𝐶 ∈ ℂ))
73		ppncan 8199	. . . . . . . . . . . . 13 ⊢ ((𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ ∧ 𝐶 ∈ ℂ) → ((𝐶 + 𝐷) + (𝐶 − 𝐷)) = (𝐶 + 𝐶))
74	73	oveq2d 5891	. . . . . . . . . . . 12 ⊢ ((𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ ∧ 𝐶 ∈ ℂ) → ((𝐴 + 𝐵) + ((𝐶 + 𝐷) + (𝐶 − 𝐷))) = ((𝐴 + 𝐵) + (𝐶 + 𝐶)))
75	72, 74	syl 14	. . . . . . . . . . 11 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((𝐴 + 𝐵) + ((𝐶 + 𝐷) + (𝐶 − 𝐷))) = ((𝐴 + 𝐵) + (𝐶 + 𝐶)))
76		simp1 997	. . . . . . . . . . . 12 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ))
77	69, 69	jca 306	. . . . . . . . . . . . 13 ⊢ ((𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) → (𝐶 ∈ ℂ ∧ 𝐶 ∈ ℂ))
78	77	3ad2ant2 1019	. . . . . . . . . . . 12 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (𝐶 ∈ ℂ ∧ 𝐶 ∈ ℂ))
79		add4 8118	. . . . . . . . . . . 12 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐶 ∈ ℂ)) → ((𝐴 + 𝐵) + (𝐶 + 𝐶)) = ((𝐴 + 𝐶) + (𝐵 + 𝐶)))
80	76, 78, 79	syl2anc 411	. . . . . . . . . . 11 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((𝐴 + 𝐵) + (𝐶 + 𝐶)) = ((𝐴 + 𝐶) + (𝐵 + 𝐶)))
81		addcl 7936	. . . . . . . . . . . . . . 15 ⊢ ((𝐴 ∈ ℂ ∧ 𝐶 ∈ ℂ) → (𝐴 + 𝐶) ∈ ℂ)
82	81	ad2ant2r 509	. . . . . . . . . . . . . 14 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → (𝐴 + 𝐶) ∈ ℂ)
83		addcl 7936	. . . . . . . . . . . . . . 15 ⊢ ((𝐵 ∈ ℂ ∧ 𝐶 ∈ ℂ) → (𝐵 + 𝐶) ∈ ℂ)
84	83	ad2ant2lr 510	. . . . . . . . . . . . . 14 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → (𝐵 + 𝐶) ∈ ℂ)
85	82, 84	jca 306	. . . . . . . . . . . . 13 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → ((𝐴 + 𝐶) ∈ ℂ ∧ (𝐵 + 𝐶) ∈ ℂ))
86	85	3adant3 1017	. . . . . . . . . . . 12 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((𝐴 + 𝐶) ∈ ℂ ∧ (𝐵 + 𝐶) ∈ ℂ))
87		addcom 8094	. . . . . . . . . . . 12 ⊢ (((𝐴 + 𝐶) ∈ ℂ ∧ (𝐵 + 𝐶) ∈ ℂ) → ((𝐴 + 𝐶) + (𝐵 + 𝐶)) = ((𝐵 + 𝐶) + (𝐴 + 𝐶)))
88	86, 87	syl 14	. . . . . . . . . . 11 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((𝐴 + 𝐶) + (𝐵 + 𝐶)) = ((𝐵 + 𝐶) + (𝐴 + 𝐶)))
89	75, 80, 88	3eqtrd 2214	. . . . . . . . . 10 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((𝐴 + 𝐵) + ((𝐶 + 𝐷) + (𝐶 − 𝐷))) = ((𝐵 + 𝐶) + (𝐴 + 𝐶)))
90	66, 68, 89	3eqtr3rd 2219	. . . . . . . . 9 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((𝐵 + 𝐶) + (𝐴 + 𝐶)) = (π + (𝐶 − 𝐷)))
91		picn 14211	. . . . . . . . . . 11 ⊢ π ∈ ℂ
92		addcom 8094	. . . . . . . . . . 11 ⊢ ((π ∈ ℂ ∧ (𝐶 − 𝐷) ∈ ℂ) → (π + (𝐶 − 𝐷)) = ((𝐶 − 𝐷) + π))
93	91, 28, 92	sylancr 414	. . . . . . . . . 10 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → (π + (𝐶 − 𝐷)) = ((𝐶 − 𝐷) + π))
94	93	3adant3 1017	. . . . . . . . 9 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (π + (𝐶 − 𝐷)) = ((𝐶 − 𝐷) + π))
95	90, 94	eqtrd 2210	. . . . . . . 8 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((𝐵 + 𝐶) + (𝐴 + 𝐶)) = ((𝐶 − 𝐷) + π))
96	95	fveq2d 5520	. . . . . . 7 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (cos‘((𝐵 + 𝐶) + (𝐴 + 𝐶))) = (cos‘((𝐶 − 𝐷) + π)))
97		cosppi 14242	. . . . . . . . 9 ⊢ ((𝐶 − 𝐷) ∈ ℂ → (cos‘((𝐶 − 𝐷) + π)) = -(cos‘(𝐶 − 𝐷)))
98	28, 97	syl 14	. . . . . . . 8 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → (cos‘((𝐶 − 𝐷) + π)) = -(cos‘(𝐶 − 𝐷)))
99	98	3adant3 1017	. . . . . . 7 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (cos‘((𝐶 − 𝐷) + π)) = -(cos‘(𝐶 − 𝐷)))
100	96, 99	eqtrd 2210	. . . . . 6 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (cos‘((𝐵 + 𝐶) + (𝐴 + 𝐶))) = -(cos‘(𝐶 − 𝐷)))
101	61, 100	oveq12d 5893	. . . . 5 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((cos‘((𝐵 + 𝐶) − (𝐴 + 𝐶))) − (cos‘((𝐵 + 𝐶) + (𝐴 + 𝐶)))) = ((cos‘(𝐵 − 𝐴)) − -(cos‘(𝐶 − 𝐷))))
102		subcl 8156	. . . . . . . . . 10 ⊢ ((𝐵 ∈ ℂ ∧ 𝐴 ∈ ℂ) → (𝐵 − 𝐴) ∈ ℂ)
103	102	ancoms 268	. . . . . . . . 9 ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) → (𝐵 − 𝐴) ∈ ℂ)
104	103	adantr 276	. . . . . . . 8 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → (𝐵 − 𝐴) ∈ ℂ)
105	104	coscld 11719	. . . . . . 7 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → (cos‘(𝐵 − 𝐴)) ∈ ℂ)
106	105, 29	subnegd 8275	. . . . . 6 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → ((cos‘(𝐵 − 𝐴)) − -(cos‘(𝐶 − 𝐷))) = ((cos‘(𝐵 − 𝐴)) + (cos‘(𝐶 − 𝐷))))
107	106	3adant3 1017	. . . . 5 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((cos‘(𝐵 − 𝐴)) − -(cos‘(𝐶 − 𝐷))) = ((cos‘(𝐵 − 𝐴)) + (cos‘(𝐶 − 𝐷))))
108	101, 107	eqtrd 2210	. . . 4 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((cos‘((𝐵 + 𝐶) − (𝐴 + 𝐶))) − (cos‘((𝐵 + 𝐶) + (𝐴 + 𝐶)))) = ((cos‘(𝐵 − 𝐴)) + (cos‘(𝐶 − 𝐷))))
109	108	oveq1d 5890	. . 3 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (((cos‘((𝐵 + 𝐶) − (𝐴 + 𝐶))) − (cos‘((𝐵 + 𝐶) + (𝐴 + 𝐶)))) / 2) = (((cos‘(𝐵 − 𝐴)) + (cos‘(𝐶 − 𝐷))) / 2))
110		sinmul 11752	. . . . 5 ⊢ (((𝐵 + 𝐶) ∈ ℂ ∧ (𝐴 + 𝐶) ∈ ℂ) → ((sin‘(𝐵 + 𝐶)) · (sin‘(𝐴 + 𝐶))) = (((cos‘((𝐵 + 𝐶) − (𝐴 + 𝐶))) − (cos‘((𝐵 + 𝐶) + (𝐴 + 𝐶)))) / 2))
111	84, 82, 110	syl2anc 411	. . . 4 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → ((sin‘(𝐵 + 𝐶)) · (sin‘(𝐴 + 𝐶))) = (((cos‘((𝐵 + 𝐶) − (𝐴 + 𝐶))) − (cos‘((𝐵 + 𝐶) + (𝐴 + 𝐶)))) / 2))
112	111	3adant3 1017	. . 3 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((sin‘(𝐵 + 𝐶)) · (sin‘(𝐴 + 𝐶))) = (((cos‘((𝐵 + 𝐶) − (𝐴 + 𝐶))) − (cos‘((𝐵 + 𝐶) + (𝐴 + 𝐶)))) / 2))
113		cosneg 11735	. . . . . . . 8 ⊢ ((𝐴 − 𝐵) ∈ ℂ → (cos‘-(𝐴 − 𝐵)) = (cos‘(𝐴 − 𝐵)))
114	36, 113	syl 14	. . . . . . 7 ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) → (cos‘-(𝐴 − 𝐵)) = (cos‘(𝐴 − 𝐵)))
115		negsubdi2 8216	. . . . . . . 8 ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) → -(𝐴 − 𝐵) = (𝐵 − 𝐴))
116	115	fveq2d 5520	. . . . . . 7 ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) → (cos‘-(𝐴 − 𝐵)) = (cos‘(𝐵 − 𝐴)))
117	114, 116	eqtr3d 2212	. . . . . 6 ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) → (cos‘(𝐴 − 𝐵)) = (cos‘(𝐵 − 𝐴)))
118	117	3ad2ant1 1018	. . . . 5 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (cos‘(𝐴 − 𝐵)) = (cos‘(𝐵 − 𝐴)))
119	118	oveq1d 5890	. . . 4 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((cos‘(𝐴 − 𝐵)) + (cos‘(𝐶 − 𝐷))) = ((cos‘(𝐵 − 𝐴)) + (cos‘(𝐶 − 𝐷))))
120	119	oveq1d 5890	. . 3 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (((cos‘(𝐴 − 𝐵)) + (cos‘(𝐶 − 𝐷))) / 2) = (((cos‘(𝐵 − 𝐴)) + (cos‘(𝐶 − 𝐷))) / 2))
121	109, 112, 120	3eqtr4d 2220	. 2 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → ((sin‘(𝐵 + 𝐶)) · (sin‘(𝐴 + 𝐶))) = (((cos‘(𝐴 − 𝐵)) + (cos‘(𝐶 − 𝐷))) / 2))
122	50, 55, 121	3eqtr4d 2220	1 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ) ∧ ((𝐴 + 𝐵) + (𝐶 + 𝐷)) = π) → (((sin‘𝐴) · (sin‘𝐵)) + ((sin‘𝐶) · (sin‘𝐷))) = ((sin‘(𝐵 + 𝐶)) · (sin‘(𝐴 + 𝐶))))

Colors of variables: wff set class

Syntax hints: → wi 4 ∧ wa 104 ∧ w3a 978 = wceq 1353 ∈ wcel 2148 class class class wbr 4004 ‘cfv 5217 (class class class)co 5875 ℂcc 7809 0cc0 7811 + caddc 7814 · cmul 7816 − cmin 8128 -cneg 8129 # cap 8538 / cdiv 8629 2c2 8970 sincsin 11652 cosccos 11653 πcpi 11655

This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-ia1 106 ax-ia2 107 ax-ia3 108 ax-in1 614 ax-in2 615 ax-io 709 ax-5 1447 ax-7 1448 ax-gen 1449 ax-ie1 1493 ax-ie2 1494 ax-8 1504 ax-10 1505 ax-11 1506 ax-i12 1507 ax-bndl 1509 ax-4 1510 ax-17 1526 ax-i9 1530 ax-ial 1534 ax-i5r 1535 ax-13 2150 ax-14 2151 ax-ext 2159 ax-coll 4119 ax-sep 4122 ax-nul 4130 ax-pow 4175 ax-pr 4210 ax-un 4434 ax-setind 4537 ax-iinf 4588 ax-cnex 7902 ax-resscn 7903 ax-1cn 7904 ax-1re 7905 ax-icn 7906 ax-addcl 7907 ax-addrcl 7908 ax-mulcl 7909 ax-mulrcl 7910 ax-addcom 7911 ax-mulcom 7912 ax-addass 7913 ax-mulass 7914 ax-distr 7915 ax-i2m1 7916 ax-0lt1 7917 ax-1rid 7918 ax-0id 7919 ax-rnegex 7920 ax-precex 7921 ax-cnre 7922 ax-pre-ltirr 7923 ax-pre-ltwlin 7924 ax-pre-lttrn 7925 ax-pre-apti 7926 ax-pre-ltadd 7927 ax-pre-mulgt0 7928 ax-pre-mulext 7929 ax-arch 7930 ax-caucvg 7931 ax-pre-suploc 7932 ax-addf 7933 ax-mulf 7934

This theorem depends on definitions: df-bi 117 df-stab 831 df-dc 835 df-3or 979 df-3an 980 df-tru 1356 df-fal 1359 df-nf 1461 df-sb 1763 df-eu 2029 df-mo 2030 df-clab 2164 df-cleq 2170 df-clel 2173 df-nfc 2308 df-ne 2348 df-nel 2443 df-ral 2460 df-rex 2461 df-reu 2462 df-rmo 2463 df-rab 2464 df-v 2740 df-sbc 2964 df-csb 3059 df-dif 3132 df-un 3134 df-in 3136 df-ss 3143 df-nul 3424 df-if 3536 df-pw 3578 df-sn 3599 df-pr 3600 df-op 3602 df-uni 3811 df-int 3846 df-iun 3889 df-disj 3982 df-br 4005 df-opab 4066 df-mpt 4067 df-tr 4103 df-id 4294 df-po 4297 df-iso 4298 df-iord 4367 df-on 4369 df-ilim 4370 df-suc 4372 df-iom 4591 df-xp 4633 df-rel 4634 df-cnv 4635 df-co 4636 df-dm 4637 df-rn 4638 df-res 4639 df-ima 4640 df-iota 5179 df-fun 5219 df-fn 5220 df-f 5221 df-f1 5222 df-fo 5223 df-f1o 5224 df-fv 5225 df-isom 5226 df-riota 5831 df-ov 5878 df-oprab 5879 df-mpo 5880 df-of 6083 df-1st 6141 df-2nd 6142 df-recs 6306 df-irdg 6371 df-frec 6392 df-1o 6417 df-oadd 6421 df-er 6535 df-map 6650 df-pm 6651 df-en 6741 df-dom 6742 df-fin 6743 df-sup 6983 df-inf 6984 df-pnf 7994 df-mnf 7995 df-xr 7996 df-ltxr 7997 df-le 7998 df-sub 8130 df-neg 8131 df-reap 8532 df-ap 8539 df-div 8630 df-inn 8920 df-2 8978 df-3 8979 df-4 8980 df-5 8981 df-6 8982 df-7 8983 df-8 8984 df-9 8985 df-n0 9177 df-z 9254 df-uz 9529 df-q 9620 df-rp 9654 df-xneg 9772 df-xadd 9773 df-ioo 9892 df-ioc 9893 df-ico 9894 df-icc 9895 df-fz 10009 df-fzo 10143 df-seqfrec 10446 df-exp 10520 df-fac 10706 df-bc 10728 df-ihash 10756 df-shft 10824 df-cj 10851 df-re 10852 df-im 10853 df-rsqrt 11007 df-abs 11008 df-clim 11287 df-sumdc 11362 df-ef 11656 df-sin 11658 df-cos 11659 df-pi 11661 df-rest 12690 df-topgen 12709 df-psmet 13450 df-xmet 13451 df-met 13452 df-bl 13453 df-mopn 13454 df-top 13501 df-topon 13514 df-bases 13546 df-ntr 13599 df-cn 13691 df-cnp 13692 df-tx 13756 df-cncf 14061 df-limced 14128 df-dvap 14129

This theorem is referenced by: (None)

W3C validator