Theorem apreim 8931

Description: Complex apartness in terms of real and imaginary parts. (Contributed by Jim Kingdon, 12-Feb-2020.)

Assertion

Ref	Expression
apreim	|- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( ( A + ( _i x. B ) ) # ( C + ( _i x. D ) ) <-> ( A # C \/ B # D ) ) )

Proof of Theorem apreim

Dummy variables r s t u x y are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		simpll 531	. . . . . 6 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> A e. RR )
2	1	recnd 8354	. . . . 5 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> A e. CC )
3		ax-icn 8274	. . . . . . 7 |- _i e. CC
4	3	a1i 9	. . . . . 6 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> _i e. CC )
5		simplr 533	. . . . . . 7 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> B e. RR )
6	5	recnd 8354	. . . . . 6 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> B e. CC )
7	4, 6	mulcld 8346	. . . . 5 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( _i x. B ) e. CC )
8	2, 7	addcld 8345	. . . 4 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( A + ( _i x. B ) ) e. CC )
9		simprl 535	. . . . . 6 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> C e. RR )
10	9	recnd 8354	. . . . 5 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> C e. CC )
11		simprr 537	. . . . . . 7 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> D e. RR )
12	11	recnd 8354	. . . . . 6 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> D e. CC )
13	4, 12	mulcld 8346	. . . . 5 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( _i x. D ) e. CC )
14	10, 13	addcld 8345	. . . 4 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( C + ( _i x. D ) ) e. CC )
15		eqeq1 2245	. . . . . . . . 9 |- ( x = ( A + ( _i x. B ) ) -> ( x = ( r + ( _i x. s ) ) <-> ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) ) )
16	15	anbi1d 469	. . . . . . . 8 |- ( x = ( A + ( _i x. B ) ) -> ( ( x = ( r + ( _i x. s ) ) /\ y = ( t + ( _i x. u ) ) ) <-> ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ y = ( t + ( _i x. u ) ) ) ) )
17	16	anbi1d 469	. . . . . . 7 |- ( x = ( A + ( _i x. B ) ) -> ( ( ( x = ( r + ( _i x. s ) ) /\ y = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) <-> ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ y = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) )
18	17	2rexbidv 2575	. . . . . 6 |- ( x = ( A + ( _i x. B ) ) -> ( E. t e. RR E. u e. RR ( ( x = ( r + ( _i x. s ) ) /\ y = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) <-> E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ y = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) )
19	18	2rexbidv 2575	. . . . 5 |- ( x = ( A + ( _i x. B ) ) -> ( E. r e. RR E. s e. RR E. t e. RR E. u e. RR ( ( x = ( r + ( _i x. s ) ) /\ y = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) <-> E. r e. RR E. s e. RR E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ y = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) )
20		eqeq1 2245	. . . . . . . . 9 |- ( y = ( C + ( _i x. D ) ) -> ( y = ( t + ( _i x. u ) ) <-> ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) )
21	20	anbi2d 468	. . . . . . . 8 |- ( y = ( C + ( _i x. D ) ) -> ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ y = ( t + ( _i x. u ) ) ) <-> ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) ) )
22	21	anbi1d 469	. . . . . . 7 |- ( y = ( C + ( _i x. D ) ) -> ( ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ y = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) <-> ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) )
23	22	2rexbidv 2575	. . . . . 6 |- ( y = ( C + ( _i x. D ) ) -> ( E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ y = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) <-> E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) )
24	23	2rexbidv 2575	. . . . 5 |- ( y = ( C + ( _i x. D ) ) -> ( E. r e. RR E. s e. RR E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ y = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) <-> E. r e. RR E. s e. RR E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) )
25		df-ap 8910	. . . . 5 |- # = { <. x , y >. | E. r e. RR E. s e. RR E. t e. RR E. u e. RR ( ( x = ( r + ( _i x. s ) ) /\ y = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) }
26	19, 24, 25	brabg 4411	. . . 4 |- ( ( ( A + ( _i x. B ) ) e. CC /\ ( C + ( _i x. D ) ) e. CC ) -> ( ( A + ( _i x. B ) ) # ( C + ( _i x. D ) ) <-> E. r e. RR E. s e. RR E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) )
27	8, 14, 26	syl2anc 415	. . 3 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( ( A + ( _i x. B ) ) # ( C + ( _i x. D ) ) <-> E. r e. RR E. s e. RR E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) )
28		simprr 537	. . . . . . 7 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> ( r #ℝ t \/ s #ℝ u ) )
29	1	ad3antrrr 496	. . . . . . . . . 10 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> A e. RR )
30	9	ad3antrrr 496	. . . . . . . . . 10 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> C e. RR )
31		apreap 8915	. . . . . . . . . 10 |- ( ( A e. RR /\ C e. RR ) -> ( A # C <-> A #ℝ C ) )
32	29, 30, 31	syl2anc 415	. . . . . . . . 9 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> ( A # C <-> A #ℝ C ) )
33	5	ad3antrrr 496	. . . . . . . . . 10 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> B e. RR )
34	11	ad3antrrr 496	. . . . . . . . . 10 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> D e. RR )
35		apreap 8915	. . . . . . . . . 10 |- ( ( B e. RR /\ D e. RR ) -> ( B # D <-> B #ℝ D ) )
36	33, 34, 35	syl2anc 415	. . . . . . . . 9 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> ( B # D <-> B #ℝ D ) )
37	32, 36	orbi12d 805	. . . . . . . 8 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> ( ( A # C \/ B # D ) <-> ( A #ℝ C \/ B #ℝ D ) ) )
38		simprll 543	. . . . . . . . . . . 12 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) )
39		simpllr 540	. . . . . . . . . . . . 13 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> ( r e. RR /\ s e. RR ) )
40		cru 8930	. . . . . . . . . . . . 13 |- ( ( ( A e. RR /\ B e. RR ) /\ ( r e. RR /\ s e. RR ) ) -> ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) <-> ( A = r /\ B = s ) ) )
41	29, 33, 39, 40	syl21anc 1277	. . . . . . . . . . . 12 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) <-> ( A = r /\ B = s ) ) )
42	38, 41	mpbid 147	. . . . . . . . . . 11 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> ( A = r /\ B = s ) )
43	42	simpld 112	. . . . . . . . . 10 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> A = r )
44		simprlr 544	. . . . . . . . . . . 12 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) )
45		simplr 533	. . . . . . . . . . . . 13 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> ( t e. RR /\ u e. RR ) )
46		cru 8930	. . . . . . . . . . . . 13 |- ( ( ( C e. RR /\ D e. RR ) /\ ( t e. RR /\ u e. RR ) ) -> ( ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) <-> ( C = t /\ D = u ) ) )
47	30, 34, 45, 46	syl21anc 1277	. . . . . . . . . . . 12 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> ( ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) <-> ( C = t /\ D = u ) ) )
48	44, 47	mpbid 147	. . . . . . . . . . 11 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> ( C = t /\ D = u ) )
49	48	simpld 112	. . . . . . . . . 10 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> C = t )
50	43, 49	breq12d 4143	. . . . . . . . 9 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> ( A #ℝ C <-> r #ℝ t ) )
51	42	simprd 114	. . . . . . . . . 10 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> B = s )
52	48	simprd 114	. . . . . . . . . 10 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> D = u )
53	51, 52	breq12d 4143	. . . . . . . . 9 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> ( B #ℝ D <-> s #ℝ u ) )
54	50, 53	orbi12d 805	. . . . . . . 8 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> ( ( A #ℝ C \/ B #ℝ D ) <-> ( r #ℝ t \/ s #ℝ u ) ) )
55	37, 54	bitrd 188	. . . . . . 7 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> ( ( A # C \/ B # D ) <-> ( r #ℝ t \/ s #ℝ u ) ) )
56	28, 55	mpbird 167	. . . . . 6 |- ( ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) /\ ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) -> ( A # C \/ B # D ) )
57	56	ex 115	. . . . 5 |- ( ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) /\ ( t e. RR /\ u e. RR ) ) -> ( ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) -> ( A # C \/ B # D ) ) )
58	57	rexlimdvva 2676	. . . 4 |- ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( r e. RR /\ s e. RR ) ) -> ( E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) -> ( A # C \/ B # D ) ) )
59	58	rexlimdvva 2676	. . 3 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( E. r e. RR E. s e. RR E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) -> ( A # C \/ B # D ) ) )
60	27, 59	sylbid 150	. 2 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( ( A + ( _i x. B ) ) # ( C + ( _i x. D ) ) -> ( A # C \/ B # D ) ) )
61	31	ad2ant2r 513	. . . . . 6 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( A # C <-> A #ℝ C ) )
62	35	ad2ant2l 512	. . . . . 6 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( B # D <-> B #ℝ D ) )
63	61, 62	orbi12d 805	. . . . 5 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( ( A # C \/ B # D ) <-> ( A #ℝ C \/ B #ℝ D ) ) )
64	63	pm5.32i 458	. . . 4 |- ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( A # C \/ B # D ) ) <-> ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( A #ℝ C \/ B #ℝ D ) ) )
65		eqid 2238	. . . . . . . . . . . 12 |- ( A + ( _i x. B ) ) = ( A + ( _i x. B ) )
66		eqid 2238	. . . . . . . . . . . 12 |- ( C + ( _i x. D ) ) = ( C + ( _i x. D ) )
67	65, 66	pm3.2i 272	. . . . . . . . . . 11 |- ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( C + ( _i x. D ) ) )
68	67	biantrur 303	. . . . . . . . . 10 |- ( ( A #ℝ C \/ B #ℝ D ) <-> ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( C + ( _i x. D ) ) ) /\ ( A #ℝ C \/ B #ℝ D ) ) )
69		oveq1 6092	. . . . . . . . . . . . . 14 |- ( t = C -> ( t + ( _i x. u ) ) = ( C + ( _i x. u ) ) )
70	69	eqeq2d 2250	. . . . . . . . . . . . 13 |- ( t = C -> ( ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) <-> ( C + ( _i x. D ) ) = ( C + ( _i x. u ) ) ) )
71	70	anbi2d 468	. . . . . . . . . . . 12 |- ( t = C -> ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) <-> ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( C + ( _i x. u ) ) ) ) )
72		breq2 4134	. . . . . . . . . . . . 13 |- ( t = C -> ( A #ℝ t <-> A #ℝ C ) )
73	72	orbi1d 803	. . . . . . . . . . . 12 |- ( t = C -> ( ( A #ℝ t \/ B #ℝ u ) <-> ( A #ℝ C \/ B #ℝ u ) ) )
74	71, 73	anbi12d 477	. . . . . . . . . . 11 |- ( t = C -> ( ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( A #ℝ t \/ B #ℝ u ) ) <-> ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( C + ( _i x. u ) ) ) /\ ( A #ℝ C \/ B #ℝ u ) ) ) )
75		oveq2 6093	. . . . . . . . . . . . . . 15 |- ( u = D -> ( _i x. u ) = ( _i x. D ) )
76	75	oveq2d 6101	. . . . . . . . . . . . . 14 |- ( u = D -> ( C + ( _i x. u ) ) = ( C + ( _i x. D ) ) )
77	76	eqeq2d 2250	. . . . . . . . . . . . 13 |- ( u = D -> ( ( C + ( _i x. D ) ) = ( C + ( _i x. u ) ) <-> ( C + ( _i x. D ) ) = ( C + ( _i x. D ) ) ) )
78	77	anbi2d 468	. . . . . . . . . . . 12 |- ( u = D -> ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( C + ( _i x. u ) ) ) <-> ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( C + ( _i x. D ) ) ) ) )
79		breq2 4134	. . . . . . . . . . . . 13 |- ( u = D -> ( B #ℝ u <-> B #ℝ D ) )
80	79	orbi2d 802	. . . . . . . . . . . 12 |- ( u = D -> ( ( A #ℝ C \/ B #ℝ u ) <-> ( A #ℝ C \/ B #ℝ D ) ) )
81	78, 80	anbi12d 477	. . . . . . . . . . 11 |- ( u = D -> ( ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( C + ( _i x. u ) ) ) /\ ( A #ℝ C \/ B #ℝ u ) ) <-> ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( C + ( _i x. D ) ) ) /\ ( A #ℝ C \/ B #ℝ D ) ) ) )
82	74, 81	rspc2ev 2945	. . . . . . . . . 10 |- ( ( C e. RR /\ D e. RR /\ ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( C + ( _i x. D ) ) ) /\ ( A #ℝ C \/ B #ℝ D ) ) ) -> E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( A #ℝ t \/ B #ℝ u ) ) )
83	68, 82	syl3an3b 1316	. . . . . . . . 9 |- ( ( C e. RR /\ D e. RR /\ ( A #ℝ C \/ B #ℝ D ) ) -> E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( A #ℝ t \/ B #ℝ u ) ) )
84	83	3expa 1234	. . . . . . . 8 |- ( ( ( C e. RR /\ D e. RR ) /\ ( A #ℝ C \/ B #ℝ D ) ) -> E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( A #ℝ t \/ B #ℝ u ) ) )
85		oveq1 6092	. . . . . . . . . . . . 13 |- ( r = A -> ( r + ( _i x. s ) ) = ( A + ( _i x. s ) ) )
86	85	eqeq2d 2250	. . . . . . . . . . . 12 |- ( r = A -> ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) <-> ( A + ( _i x. B ) ) = ( A + ( _i x. s ) ) ) )
87	86	anbi1d 469	. . . . . . . . . . 11 |- ( r = A -> ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) <-> ( ( A + ( _i x. B ) ) = ( A + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) ) )
88		breq1 4133	. . . . . . . . . . . 12 |- ( r = A -> ( r #ℝ t <-> A #ℝ t ) )
89	88	orbi1d 803	. . . . . . . . . . 11 |- ( r = A -> ( ( r #ℝ t \/ s #ℝ u ) <-> ( A #ℝ t \/ s #ℝ u ) ) )
90	87, 89	anbi12d 477	. . . . . . . . . 10 |- ( r = A -> ( ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) <-> ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( A #ℝ t \/ s #ℝ u ) ) ) )
91	90	2rexbidv 2575	. . . . . . . . 9 |- ( r = A -> ( E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) <-> E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( A #ℝ t \/ s #ℝ u ) ) ) )
92		oveq2 6093	. . . . . . . . . . . . . 14 |- ( s = B -> ( _i x. s ) = ( _i x. B ) )
93	92	oveq2d 6101	. . . . . . . . . . . . 13 |- ( s = B -> ( A + ( _i x. s ) ) = ( A + ( _i x. B ) ) )
94	93	eqeq2d 2250	. . . . . . . . . . . 12 |- ( s = B -> ( ( A + ( _i x. B ) ) = ( A + ( _i x. s ) ) <-> ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) ) )
95	94	anbi1d 469	. . . . . . . . . . 11 |- ( s = B -> ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) <-> ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) ) )
96		breq1 4133	. . . . . . . . . . . 12 |- ( s = B -> ( s #ℝ u <-> B #ℝ u ) )
97	96	orbi2d 802	. . . . . . . . . . 11 |- ( s = B -> ( ( A #ℝ t \/ s #ℝ u ) <-> ( A #ℝ t \/ B #ℝ u ) ) )
98	95, 97	anbi12d 477	. . . . . . . . . 10 |- ( s = B -> ( ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( A #ℝ t \/ s #ℝ u ) ) <-> ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( A #ℝ t \/ B #ℝ u ) ) ) )
99	98	2rexbidv 2575	. . . . . . . . 9 |- ( s = B -> ( E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( A #ℝ t \/ s #ℝ u ) ) <-> E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( A #ℝ t \/ B #ℝ u ) ) ) )
100	91, 99	rspc2ev 2945	. . . . . . . 8 |- ( ( A e. RR /\ B e. RR /\ E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( A + ( _i x. B ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( A #ℝ t \/ B #ℝ u ) ) ) -> E. r e. RR E. s e. RR E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) )
101	84, 100	syl3an3 1313	. . . . . . 7 |- ( ( A e. RR /\ B e. RR /\ ( ( C e. RR /\ D e. RR ) /\ ( A #ℝ C \/ B #ℝ D ) ) ) -> E. r e. RR E. s e. RR E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) )
102	101	3expa 1234	. . . . . 6 |- ( ( ( A e. RR /\ B e. RR ) /\ ( ( C e. RR /\ D e. RR ) /\ ( A #ℝ C \/ B #ℝ D ) ) ) -> E. r e. RR E. s e. RR E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) )
103	102	anassrs 404	. . . . 5 |- ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( A #ℝ C \/ B #ℝ D ) ) -> E. r e. RR E. s e. RR E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) )
104	27	adantr 276	. . . . 5 |- ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( A #ℝ C \/ B #ℝ D ) ) -> ( ( A + ( _i x. B ) ) # ( C + ( _i x. D ) ) <-> E. r e. RR E. s e. RR E. t e. RR E. u e. RR ( ( ( A + ( _i x. B ) ) = ( r + ( _i x. s ) ) /\ ( C + ( _i x. D ) ) = ( t + ( _i x. u ) ) ) /\ ( r #ℝ t \/ s #ℝ u ) ) ) )
105	103, 104	mpbird 167	. . . 4 |- ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( A #ℝ C \/ B #ℝ D ) ) -> ( A + ( _i x. B ) ) # ( C + ( _i x. D ) ) )
106	64, 105	sylbi 121	. . 3 |- ( ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) /\ ( A # C \/ B # D ) ) -> ( A + ( _i x. B ) ) # ( C + ( _i x. D ) ) )
107	106	ex 115	. 2 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( ( A # C \/ B # D ) -> ( A + ( _i x. B ) ) # ( C + ( _i x. D ) ) ) )
108	60, 107	impbid 129	1 |- ( ( ( A e. RR /\ B e. RR ) /\ ( C e. RR /\ D e. RR ) ) -> ( ( A + ( _i x. B ) ) # ( C + ( _i x. D ) ) <-> ( A # C \/ B # D ) ) )

This proof depends on syntax axioms:   -> wi 4   /\ wa 104   <-> wb 105   \/ wo 720   = wceq 1402   e. wcel 2209   E.wrex 2529   class class class wbr 4130  (class class class)co 6085   CCcc 8177   RRcr 8178   _ici 8181   + caddc 8182   x. cmul 8184   #_ℝ creap 8902   # cap 8909

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-sep 4249  ax-pow 4311  ax-pr 4346  ax-un 4578  ax-setind 4684  ax-cnex 8270  ax-resscn 8271  ax-1cn 8272  ax-1re 8273  ax-icn 8274  ax-addcl 8275  ax-addrcl 8276  ax-mulcl 8277  ax-mulrcl 8278  ax-addcom 8279  ax-mulcom 8280  ax-addass 8281  ax-mulass 8282  ax-distr 8283  ax-i2m1 8284  ax-0lt1 8285  ax-1rid 8286  ax-0id 8287  ax-rnegex 8288  ax-precex 8289  ax-cnre 8290  ax-pre-ltirr 8291  ax-pre-lttrn 8293  ax-pre-apti 8294  ax-pre-ltadd 8295  ax-pre-mulgt0 8296

This proof depends on definitions:  df-bi 117  df-3an 1011  df-tru 1405  df-fal 1408  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ne 2421  df-nel 2516  df-ral 2533  df-rex 2534  df-reu 2535  df-rab 2537  df-v 2823  df-sbc 3052  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-pw 3690  df-sn 3715  df-pr 3716  df-op 3718  df-uni 3936  df-br 4131  df-opab 4193  df-id 4438  df-xp 4780  df-rel 4781  df-cnv 4782  df-co 4783  df-dm 4784  df-iota 5337  df-fun 5379  df-fv 5385  df-riota 6038  df-ov 6088  df-oprab 6089  df-mpo 6090  df-pnf 8362  df-mnf 8363  df-ltxr 8365  df-sub 8499  df-neg 8500  df-reap 8903  df-ap 8910

This theorem is used by:  apirr  8933  apsym  8934  apcotr  8935  apadd1  8936  apneg  8939  mulext1  8940  apti  8950  recexaplem2  8980  crap0  9288  iap0  9528  cjap  11672  cnreim  11744  absext  11829