Metamath Proof Explorer


Theorem atantan

Description: The arctangent function is an inverse to tan . (Contributed by Mario Carneiro, 5-Apr-2015)

Ref Expression
Assertion atantan
|- ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( arctan ` ( tan ` A ) ) = A )

Proof

Step Hyp Ref Expression
1 cosne0
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( cos ` A ) =/= 0 )
2 atandmtan
 |-  ( ( A e. CC /\ ( cos ` A ) =/= 0 ) -> ( tan ` A ) e. dom arctan )
3 1 2 syldan
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( tan ` A ) e. dom arctan )
4 atanval
 |-  ( ( tan ` A ) e. dom arctan -> ( arctan ` ( tan ` A ) ) = ( ( _i / 2 ) x. ( ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) ) ) )
5 3 4 syl
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( arctan ` ( tan ` A ) ) = ( ( _i / 2 ) x. ( ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) ) ) )
6 ax-1cn
 |-  1 e. CC
7 ax-icn
 |-  _i e. CC
8 tancl
 |-  ( ( A e. CC /\ ( cos ` A ) =/= 0 ) -> ( tan ` A ) e. CC )
9 1 8 syldan
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( tan ` A ) e. CC )
10 mulcl
 |-  ( ( _i e. CC /\ ( tan ` A ) e. CC ) -> ( _i x. ( tan ` A ) ) e. CC )
11 7 9 10 sylancr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( _i x. ( tan ` A ) ) e. CC )
12 addcl
 |-  ( ( 1 e. CC /\ ( _i x. ( tan ` A ) ) e. CC ) -> ( 1 + ( _i x. ( tan ` A ) ) ) e. CC )
13 6 11 12 sylancr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( 1 + ( _i x. ( tan ` A ) ) ) e. CC )
14 atandm2
 |-  ( ( tan ` A ) e. dom arctan <-> ( ( tan ` A ) e. CC /\ ( 1 - ( _i x. ( tan ` A ) ) ) =/= 0 /\ ( 1 + ( _i x. ( tan ` A ) ) ) =/= 0 ) )
15 3 14 sylib
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( tan ` A ) e. CC /\ ( 1 - ( _i x. ( tan ` A ) ) ) =/= 0 /\ ( 1 + ( _i x. ( tan ` A ) ) ) =/= 0 ) )
16 15 simp3d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( 1 + ( _i x. ( tan ` A ) ) ) =/= 0 )
17 13 16 logcld
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) e. CC )
18 subcl
 |-  ( ( 1 e. CC /\ ( _i x. ( tan ` A ) ) e. CC ) -> ( 1 - ( _i x. ( tan ` A ) ) ) e. CC )
19 6 11 18 sylancr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( 1 - ( _i x. ( tan ` A ) ) ) e. CC )
20 15 simp2d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( 1 - ( _i x. ( tan ` A ) ) ) =/= 0 )
21 19 20 logcld
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) e. CC )
22 17 21 negsubdi2d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> -u ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) = ( ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) ) )
23 efsub
 |-  ( ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) e. CC /\ ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) e. CC ) -> ( exp ` ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) ) = ( ( exp ` ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) ) / ( exp ` ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) ) )
24 17 21 23 syl2anc
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( exp ` ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) ) = ( ( exp ` ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) ) / ( exp ` ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) ) )
25 coscl
 |-  ( A e. CC -> ( cos ` A ) e. CC )
26 25 adantr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( cos ` A ) e. CC )
27 sincl
 |-  ( A e. CC -> ( sin ` A ) e. CC )
28 27 adantr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( sin ` A ) e. CC )
29 mulcl
 |-  ( ( _i e. CC /\ ( sin ` A ) e. CC ) -> ( _i x. ( sin ` A ) ) e. CC )
30 7 28 29 sylancr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( _i x. ( sin ` A ) ) e. CC )
31 26 30 26 1 divdird
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( ( cos ` A ) + ( _i x. ( sin ` A ) ) ) / ( cos ` A ) ) = ( ( ( cos ` A ) / ( cos ` A ) ) + ( ( _i x. ( sin ` A ) ) / ( cos ` A ) ) ) )
32 26 1 dividd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( cos ` A ) / ( cos ` A ) ) = 1 )
33 7 a1i
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> _i e. CC )
34 33 28 26 1 divassd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( _i x. ( sin ` A ) ) / ( cos ` A ) ) = ( _i x. ( ( sin ` A ) / ( cos ` A ) ) ) )
35 tanval
 |-  ( ( A e. CC /\ ( cos ` A ) =/= 0 ) -> ( tan ` A ) = ( ( sin ` A ) / ( cos ` A ) ) )
36 1 35 syldan
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( tan ` A ) = ( ( sin ` A ) / ( cos ` A ) ) )
37 36 oveq2d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( _i x. ( tan ` A ) ) = ( _i x. ( ( sin ` A ) / ( cos ` A ) ) ) )
38 34 37 eqtr4d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( _i x. ( sin ` A ) ) / ( cos ` A ) ) = ( _i x. ( tan ` A ) ) )
39 32 38 oveq12d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( ( cos ` A ) / ( cos ` A ) ) + ( ( _i x. ( sin ` A ) ) / ( cos ` A ) ) ) = ( 1 + ( _i x. ( tan ` A ) ) ) )
40 31 39 eqtrd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( ( cos ` A ) + ( _i x. ( sin ` A ) ) ) / ( cos ` A ) ) = ( 1 + ( _i x. ( tan ` A ) ) ) )
41 efival
 |-  ( A e. CC -> ( exp ` ( _i x. A ) ) = ( ( cos ` A ) + ( _i x. ( sin ` A ) ) ) )
42 41 adantr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( exp ` ( _i x. A ) ) = ( ( cos ` A ) + ( _i x. ( sin ` A ) ) ) )
43 42 oveq1d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( exp ` ( _i x. A ) ) / ( cos ` A ) ) = ( ( ( cos ` A ) + ( _i x. ( sin ` A ) ) ) / ( cos ` A ) ) )
44 eflog
 |-  ( ( ( 1 + ( _i x. ( tan ` A ) ) ) e. CC /\ ( 1 + ( _i x. ( tan ` A ) ) ) =/= 0 ) -> ( exp ` ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) ) = ( 1 + ( _i x. ( tan ` A ) ) ) )
45 13 16 44 syl2anc
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( exp ` ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) ) = ( 1 + ( _i x. ( tan ` A ) ) ) )
46 40 43 45 3eqtr4d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( exp ` ( _i x. A ) ) / ( cos ` A ) ) = ( exp ` ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) ) )
47 26 30 26 1 divsubdird
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( ( cos ` A ) - ( _i x. ( sin ` A ) ) ) / ( cos ` A ) ) = ( ( ( cos ` A ) / ( cos ` A ) ) - ( ( _i x. ( sin ` A ) ) / ( cos ` A ) ) ) )
48 32 38 oveq12d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( ( cos ` A ) / ( cos ` A ) ) - ( ( _i x. ( sin ` A ) ) / ( cos ` A ) ) ) = ( 1 - ( _i x. ( tan ` A ) ) ) )
49 47 48 eqtrd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( ( cos ` A ) - ( _i x. ( sin ` A ) ) ) / ( cos ` A ) ) = ( 1 - ( _i x. ( tan ` A ) ) ) )
50 negcl
 |-  ( A e. CC -> -u A e. CC )
51 50 adantr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> -u A e. CC )
52 efival
 |-  ( -u A e. CC -> ( exp ` ( _i x. -u A ) ) = ( ( cos ` -u A ) + ( _i x. ( sin ` -u A ) ) ) )
53 51 52 syl
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( exp ` ( _i x. -u A ) ) = ( ( cos ` -u A ) + ( _i x. ( sin ` -u A ) ) ) )
54 cosneg
 |-  ( A e. CC -> ( cos ` -u A ) = ( cos ` A ) )
55 54 adantr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( cos ` -u A ) = ( cos ` A ) )
56 sinneg
 |-  ( A e. CC -> ( sin ` -u A ) = -u ( sin ` A ) )
57 56 adantr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( sin ` -u A ) = -u ( sin ` A ) )
58 57 oveq2d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( _i x. ( sin ` -u A ) ) = ( _i x. -u ( sin ` A ) ) )
59 mulneg2
 |-  ( ( _i e. CC /\ ( sin ` A ) e. CC ) -> ( _i x. -u ( sin ` A ) ) = -u ( _i x. ( sin ` A ) ) )
60 7 28 59 sylancr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( _i x. -u ( sin ` A ) ) = -u ( _i x. ( sin ` A ) ) )
61 58 60 eqtrd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( _i x. ( sin ` -u A ) ) = -u ( _i x. ( sin ` A ) ) )
62 55 61 oveq12d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( cos ` -u A ) + ( _i x. ( sin ` -u A ) ) ) = ( ( cos ` A ) + -u ( _i x. ( sin ` A ) ) ) )
63 53 62 eqtrd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( exp ` ( _i x. -u A ) ) = ( ( cos ` A ) + -u ( _i x. ( sin ` A ) ) ) )
64 simpl
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> A e. CC )
65 mulneg2
 |-  ( ( _i e. CC /\ A e. CC ) -> ( _i x. -u A ) = -u ( _i x. A ) )
66 7 64 65 sylancr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( _i x. -u A ) = -u ( _i x. A ) )
67 66 fveq2d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( exp ` ( _i x. -u A ) ) = ( exp ` -u ( _i x. A ) ) )
68 26 30 negsubd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( cos ` A ) + -u ( _i x. ( sin ` A ) ) ) = ( ( cos ` A ) - ( _i x. ( sin ` A ) ) ) )
69 63 67 68 3eqtr3d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( exp ` -u ( _i x. A ) ) = ( ( cos ` A ) - ( _i x. ( sin ` A ) ) ) )
70 69 oveq1d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( exp ` -u ( _i x. A ) ) / ( cos ` A ) ) = ( ( ( cos ` A ) - ( _i x. ( sin ` A ) ) ) / ( cos ` A ) ) )
71 eflog
 |-  ( ( ( 1 - ( _i x. ( tan ` A ) ) ) e. CC /\ ( 1 - ( _i x. ( tan ` A ) ) ) =/= 0 ) -> ( exp ` ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) = ( 1 - ( _i x. ( tan ` A ) ) ) )
72 19 20 71 syl2anc
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( exp ` ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) = ( 1 - ( _i x. ( tan ` A ) ) ) )
73 49 70 72 3eqtr4d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( exp ` -u ( _i x. A ) ) / ( cos ` A ) ) = ( exp ` ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) )
74 46 73 oveq12d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( ( exp ` ( _i x. A ) ) / ( cos ` A ) ) / ( ( exp ` -u ( _i x. A ) ) / ( cos ` A ) ) ) = ( ( exp ` ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) ) / ( exp ` ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) ) )
75 mulcl
 |-  ( ( _i e. CC /\ A e. CC ) -> ( _i x. A ) e. CC )
76 7 64 75 sylancr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( _i x. A ) e. CC )
77 efcl
 |-  ( ( _i x. A ) e. CC -> ( exp ` ( _i x. A ) ) e. CC )
78 76 77 syl
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( exp ` ( _i x. A ) ) e. CC )
79 76 negcld
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> -u ( _i x. A ) e. CC )
80 efcl
 |-  ( -u ( _i x. A ) e. CC -> ( exp ` -u ( _i x. A ) ) e. CC )
81 79 80 syl
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( exp ` -u ( _i x. A ) ) e. CC )
82 efne0
 |-  ( -u ( _i x. A ) e. CC -> ( exp ` -u ( _i x. A ) ) =/= 0 )
83 79 82 syl
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( exp ` -u ( _i x. A ) ) =/= 0 )
84 78 81 26 83 1 divcan7d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( ( exp ` ( _i x. A ) ) / ( cos ` A ) ) / ( ( exp ` -u ( _i x. A ) ) / ( cos ` A ) ) ) = ( ( exp ` ( _i x. A ) ) / ( exp ` -u ( _i x. A ) ) ) )
85 efsub
 |-  ( ( ( _i x. A ) e. CC /\ -u ( _i x. A ) e. CC ) -> ( exp ` ( ( _i x. A ) - -u ( _i x. A ) ) ) = ( ( exp ` ( _i x. A ) ) / ( exp ` -u ( _i x. A ) ) ) )
86 76 79 85 syl2anc
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( exp ` ( ( _i x. A ) - -u ( _i x. A ) ) ) = ( ( exp ` ( _i x. A ) ) / ( exp ` -u ( _i x. A ) ) ) )
87 76 76 subnegd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( _i x. A ) - -u ( _i x. A ) ) = ( ( _i x. A ) + ( _i x. A ) ) )
88 76 2timesd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( 2 x. ( _i x. A ) ) = ( ( _i x. A ) + ( _i x. A ) ) )
89 87 88 eqtr4d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( _i x. A ) - -u ( _i x. A ) ) = ( 2 x. ( _i x. A ) ) )
90 89 fveq2d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( exp ` ( ( _i x. A ) - -u ( _i x. A ) ) ) = ( exp ` ( 2 x. ( _i x. A ) ) ) )
91 84 86 90 3eqtr2d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( ( exp ` ( _i x. A ) ) / ( cos ` A ) ) / ( ( exp ` -u ( _i x. A ) ) / ( cos ` A ) ) ) = ( exp ` ( 2 x. ( _i x. A ) ) ) )
92 24 74 91 3eqtr2d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( exp ` ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) ) = ( exp ` ( 2 x. ( _i x. A ) ) ) )
93 92 fveq2d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( log ` ( exp ` ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) ) ) = ( log ` ( exp ` ( 2 x. ( _i x. A ) ) ) ) )
94 64 adantr
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> A e. CC )
95 94 renegd
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> ( Re ` -u A ) = -u ( Re ` A ) )
96 94 recld
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> ( Re ` A ) e. RR )
97 96 renegcld
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> -u ( Re ` A ) e. RR )
98 simpr
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> ( Re ` A ) < 0 )
99 96 lt0neg1d
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> ( ( Re ` A ) < 0 <-> 0 < -u ( Re ` A ) ) )
100 98 99 mpbid
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> 0 < -u ( Re ` A ) )
101 eliooord
 |-  ( ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) -> ( -u ( _pi / 2 ) < ( Re ` A ) /\ ( Re ` A ) < ( _pi / 2 ) ) )
102 101 adantl
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( -u ( _pi / 2 ) < ( Re ` A ) /\ ( Re ` A ) < ( _pi / 2 ) ) )
103 102 simpld
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> -u ( _pi / 2 ) < ( Re ` A ) )
104 103 adantr
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> -u ( _pi / 2 ) < ( Re ` A ) )
105 halfpire
 |-  ( _pi / 2 ) e. RR
106 ltnegcon1
 |-  ( ( ( _pi / 2 ) e. RR /\ ( Re ` A ) e. RR ) -> ( -u ( _pi / 2 ) < ( Re ` A ) <-> -u ( Re ` A ) < ( _pi / 2 ) ) )
107 105 96 106 sylancr
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> ( -u ( _pi / 2 ) < ( Re ` A ) <-> -u ( Re ` A ) < ( _pi / 2 ) ) )
108 104 107 mpbid
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> -u ( Re ` A ) < ( _pi / 2 ) )
109 0xr
 |-  0 e. RR*
110 105 rexri
 |-  ( _pi / 2 ) e. RR*
111 elioo2
 |-  ( ( 0 e. RR* /\ ( _pi / 2 ) e. RR* ) -> ( -u ( Re ` A ) e. ( 0 (,) ( _pi / 2 ) ) <-> ( -u ( Re ` A ) e. RR /\ 0 < -u ( Re ` A ) /\ -u ( Re ` A ) < ( _pi / 2 ) ) ) )
112 109 110 111 mp2an
 |-  ( -u ( Re ` A ) e. ( 0 (,) ( _pi / 2 ) ) <-> ( -u ( Re ` A ) e. RR /\ 0 < -u ( Re ` A ) /\ -u ( Re ` A ) < ( _pi / 2 ) ) )
113 97 100 108 112 syl3anbrc
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> -u ( Re ` A ) e. ( 0 (,) ( _pi / 2 ) ) )
114 95 113 eqeltrd
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> ( Re ` -u A ) e. ( 0 (,) ( _pi / 2 ) ) )
115 tanregt0
 |-  ( ( -u A e. CC /\ ( Re ` -u A ) e. ( 0 (,) ( _pi / 2 ) ) ) -> 0 < ( Re ` ( tan ` -u A ) ) )
116 51 114 115 syl2an2r
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> 0 < ( Re ` ( tan ` -u A ) ) )
117 tanneg
 |-  ( ( A e. CC /\ ( cos ` A ) =/= 0 ) -> ( tan ` -u A ) = -u ( tan ` A ) )
118 1 117 syldan
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( tan ` -u A ) = -u ( tan ` A ) )
119 118 adantr
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> ( tan ` -u A ) = -u ( tan ` A ) )
120 119 fveq2d
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> ( Re ` ( tan ` -u A ) ) = ( Re ` -u ( tan ` A ) ) )
121 9 adantr
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> ( tan ` A ) e. CC )
122 121 renegd
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> ( Re ` -u ( tan ` A ) ) = -u ( Re ` ( tan ` A ) ) )
123 120 122 eqtrd
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> ( Re ` ( tan ` -u A ) ) = -u ( Re ` ( tan ` A ) ) )
124 116 123 breqtrd
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> 0 < -u ( Re ` ( tan ` A ) ) )
125 9 recld
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( Re ` ( tan ` A ) ) e. RR )
126 125 adantr
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> ( Re ` ( tan ` A ) ) e. RR )
127 126 lt0neg1d
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> ( ( Re ` ( tan ` A ) ) < 0 <-> 0 < -u ( Re ` ( tan ` A ) ) ) )
128 124 127 mpbird
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> ( Re ` ( tan ` A ) ) < 0 )
129 128 lt0ne0d
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> ( Re ` ( tan ` A ) ) =/= 0 )
130 atanlogsub
 |-  ( ( ( tan ` A ) e. dom arctan /\ ( Re ` ( tan ` A ) ) =/= 0 ) -> ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) e. ran log )
131 3 129 130 syl2an2r
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) < 0 ) -> ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) e. ran log )
132 1re
 |-  1 e. RR
133 ioossre
 |-  ( -u 1 (,) 1 ) C_ RR
134 7 a1i
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> _i e. CC )
135 11 adantr
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( _i x. ( tan ` A ) ) e. CC )
136 ine0
 |-  _i =/= 0
137 136 a1i
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> _i =/= 0 )
138 ixi
 |-  ( _i x. _i ) = -u 1
139 138 oveq1i
 |-  ( ( _i x. _i ) x. ( tan ` A ) ) = ( -u 1 x. ( tan ` A ) )
140 9 adantr
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( tan ` A ) e. CC )
141 140 mulm1d
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( -u 1 x. ( tan ` A ) ) = -u ( tan ` A ) )
142 118 adantr
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( tan ` -u A ) = -u ( tan ` A ) )
143 141 142 eqtr4d
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( -u 1 x. ( tan ` A ) ) = ( tan ` -u A ) )
144 139 143 syl5eq
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( ( _i x. _i ) x. ( tan ` A ) ) = ( tan ` -u A ) )
145 134 134 140 mulassd
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( ( _i x. _i ) x. ( tan ` A ) ) = ( _i x. ( _i x. ( tan ` A ) ) ) )
146 138 oveq1i
 |-  ( ( _i x. _i ) x. A ) = ( -u 1 x. A )
147 64 adantr
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> A e. CC )
148 147 mulm1d
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( -u 1 x. A ) = -u A )
149 146 148 syl5eq
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( ( _i x. _i ) x. A ) = -u A )
150 134 134 147 mulassd
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( ( _i x. _i ) x. A ) = ( _i x. ( _i x. A ) ) )
151 149 150 eqtr3d
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> -u A = ( _i x. ( _i x. A ) ) )
152 151 fveq2d
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( tan ` -u A ) = ( tan ` ( _i x. ( _i x. A ) ) ) )
153 144 145 152 3eqtr3d
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( _i x. ( _i x. ( tan ` A ) ) ) = ( tan ` ( _i x. ( _i x. A ) ) ) )
154 134 135 137 153 mvllmuld
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( _i x. ( tan ` A ) ) = ( ( tan ` ( _i x. ( _i x. A ) ) ) / _i ) )
155 76 adantr
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( _i x. A ) e. CC )
156 reim
 |-  ( A e. CC -> ( Re ` A ) = ( Im ` ( _i x. A ) ) )
157 156 adantr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( Re ` A ) = ( Im ` ( _i x. A ) ) )
158 157 eqeq1d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( Re ` A ) = 0 <-> ( Im ` ( _i x. A ) ) = 0 ) )
159 158 biimpa
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( Im ` ( _i x. A ) ) = 0 )
160 155 159 reim0bd
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( _i x. A ) e. RR )
161 tanhbnd
 |-  ( ( _i x. A ) e. RR -> ( ( tan ` ( _i x. ( _i x. A ) ) ) / _i ) e. ( -u 1 (,) 1 ) )
162 160 161 syl
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( ( tan ` ( _i x. ( _i x. A ) ) ) / _i ) e. ( -u 1 (,) 1 ) )
163 154 162 eqeltrd
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( _i x. ( tan ` A ) ) e. ( -u 1 (,) 1 ) )
164 133 163 sselid
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( _i x. ( tan ` A ) ) e. RR )
165 readdcl
 |-  ( ( 1 e. RR /\ ( _i x. ( tan ` A ) ) e. RR ) -> ( 1 + ( _i x. ( tan ` A ) ) ) e. RR )
166 132 164 165 sylancr
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( 1 + ( _i x. ( tan ` A ) ) ) e. RR )
167 df-neg
 |-  -u 1 = ( 0 - 1 )
168 eliooord
 |-  ( ( _i x. ( tan ` A ) ) e. ( -u 1 (,) 1 ) -> ( -u 1 < ( _i x. ( tan ` A ) ) /\ ( _i x. ( tan ` A ) ) < 1 ) )
169 163 168 syl
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( -u 1 < ( _i x. ( tan ` A ) ) /\ ( _i x. ( tan ` A ) ) < 1 ) )
170 169 simpld
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> -u 1 < ( _i x. ( tan ` A ) ) )
171 167 170 eqbrtrrid
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( 0 - 1 ) < ( _i x. ( tan ` A ) ) )
172 0red
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> 0 e. RR )
173 132 a1i
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> 1 e. RR )
174 172 173 164 ltsubadd2d
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( ( 0 - 1 ) < ( _i x. ( tan ` A ) ) <-> 0 < ( 1 + ( _i x. ( tan ` A ) ) ) ) )
175 171 174 mpbid
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> 0 < ( 1 + ( _i x. ( tan ` A ) ) ) )
176 166 175 elrpd
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( 1 + ( _i x. ( tan ` A ) ) ) e. RR+ )
177 176 relogcld
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) e. RR )
178 169 simprd
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( _i x. ( tan ` A ) ) < 1 )
179 difrp
 |-  ( ( ( _i x. ( tan ` A ) ) e. RR /\ 1 e. RR ) -> ( ( _i x. ( tan ` A ) ) < 1 <-> ( 1 - ( _i x. ( tan ` A ) ) ) e. RR+ ) )
180 164 132 179 sylancl
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( ( _i x. ( tan ` A ) ) < 1 <-> ( 1 - ( _i x. ( tan ` A ) ) ) e. RR+ ) )
181 178 180 mpbid
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( 1 - ( _i x. ( tan ` A ) ) ) e. RR+ )
182 181 relogcld
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) e. RR )
183 177 182 resubcld
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) e. RR )
184 relogrn
 |-  ( ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) e. RR -> ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) e. ran log )
185 183 184 syl
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ ( Re ` A ) = 0 ) -> ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) e. ran log )
186 64 adantr
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ 0 < ( Re ` A ) ) -> A e. CC )
187 186 recld
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ 0 < ( Re ` A ) ) -> ( Re ` A ) e. RR )
188 simpr
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ 0 < ( Re ` A ) ) -> 0 < ( Re ` A ) )
189 102 simprd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( Re ` A ) < ( _pi / 2 ) )
190 189 adantr
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ 0 < ( Re ` A ) ) -> ( Re ` A ) < ( _pi / 2 ) )
191 elioo2
 |-  ( ( 0 e. RR* /\ ( _pi / 2 ) e. RR* ) -> ( ( Re ` A ) e. ( 0 (,) ( _pi / 2 ) ) <-> ( ( Re ` A ) e. RR /\ 0 < ( Re ` A ) /\ ( Re ` A ) < ( _pi / 2 ) ) ) )
192 109 110 191 mp2an
 |-  ( ( Re ` A ) e. ( 0 (,) ( _pi / 2 ) ) <-> ( ( Re ` A ) e. RR /\ 0 < ( Re ` A ) /\ ( Re ` A ) < ( _pi / 2 ) ) )
193 187 188 190 192 syl3anbrc
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ 0 < ( Re ` A ) ) -> ( Re ` A ) e. ( 0 (,) ( _pi / 2 ) ) )
194 tanregt0
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( 0 (,) ( _pi / 2 ) ) ) -> 0 < ( Re ` ( tan ` A ) ) )
195 64 193 194 syl2an2r
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ 0 < ( Re ` A ) ) -> 0 < ( Re ` ( tan ` A ) ) )
196 195 gt0ne0d
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ 0 < ( Re ` A ) ) -> ( Re ` ( tan ` A ) ) =/= 0 )
197 3 196 130 syl2an2r
 |-  ( ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) /\ 0 < ( Re ` A ) ) -> ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) e. ran log )
198 recl
 |-  ( A e. CC -> ( Re ` A ) e. RR )
199 198 adantr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( Re ` A ) e. RR )
200 0re
 |-  0 e. RR
201 lttri4
 |-  ( ( ( Re ` A ) e. RR /\ 0 e. RR ) -> ( ( Re ` A ) < 0 \/ ( Re ` A ) = 0 \/ 0 < ( Re ` A ) ) )
202 199 200 201 sylancl
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( Re ` A ) < 0 \/ ( Re ` A ) = 0 \/ 0 < ( Re ` A ) ) )
203 131 185 197 202 mpjao3dan
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) e. ran log )
204 logef
 |-  ( ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) e. ran log -> ( log ` ( exp ` ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) ) ) = ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) )
205 203 204 syl
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( log ` ( exp ` ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) ) ) = ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) )
206 2cn
 |-  2 e. CC
207 mulcl
 |-  ( ( 2 e. CC /\ ( _i x. A ) e. CC ) -> ( 2 x. ( _i x. A ) ) e. CC )
208 206 76 207 sylancr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( 2 x. ( _i x. A ) ) e. CC )
209 picn
 |-  _pi e. CC
210 2ne0
 |-  2 =/= 0
211 divneg
 |-  ( ( _pi e. CC /\ 2 e. CC /\ 2 =/= 0 ) -> -u ( _pi / 2 ) = ( -u _pi / 2 ) )
212 209 206 210 211 mp3an
 |-  -u ( _pi / 2 ) = ( -u _pi / 2 )
213 212 103 eqbrtrrid
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( -u _pi / 2 ) < ( Re ` A ) )
214 pire
 |-  _pi e. RR
215 214 renegcli
 |-  -u _pi e. RR
216 215 a1i
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> -u _pi e. RR )
217 2re
 |-  2 e. RR
218 217 a1i
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> 2 e. RR )
219 2pos
 |-  0 < 2
220 219 a1i
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> 0 < 2 )
221 ltdivmul
 |-  ( ( -u _pi e. RR /\ ( Re ` A ) e. RR /\ ( 2 e. RR /\ 0 < 2 ) ) -> ( ( -u _pi / 2 ) < ( Re ` A ) <-> -u _pi < ( 2 x. ( Re ` A ) ) ) )
222 216 199 218 220 221 syl112anc
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( -u _pi / 2 ) < ( Re ` A ) <-> -u _pi < ( 2 x. ( Re ` A ) ) ) )
223 213 222 mpbid
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> -u _pi < ( 2 x. ( Re ` A ) ) )
224 immul2
 |-  ( ( 2 e. RR /\ ( _i x. A ) e. CC ) -> ( Im ` ( 2 x. ( _i x. A ) ) ) = ( 2 x. ( Im ` ( _i x. A ) ) ) )
225 217 76 224 sylancr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( Im ` ( 2 x. ( _i x. A ) ) ) = ( 2 x. ( Im ` ( _i x. A ) ) ) )
226 157 oveq2d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( 2 x. ( Re ` A ) ) = ( 2 x. ( Im ` ( _i x. A ) ) ) )
227 225 226 eqtr4d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( Im ` ( 2 x. ( _i x. A ) ) ) = ( 2 x. ( Re ` A ) ) )
228 223 227 breqtrrd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> -u _pi < ( Im ` ( 2 x. ( _i x. A ) ) ) )
229 remulcl
 |-  ( ( 2 e. RR /\ ( Re ` A ) e. RR ) -> ( 2 x. ( Re ` A ) ) e. RR )
230 217 199 229 sylancr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( 2 x. ( Re ` A ) ) e. RR )
231 214 a1i
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> _pi e. RR )
232 ltmuldiv2
 |-  ( ( ( Re ` A ) e. RR /\ _pi e. RR /\ ( 2 e. RR /\ 0 < 2 ) ) -> ( ( 2 x. ( Re ` A ) ) < _pi <-> ( Re ` A ) < ( _pi / 2 ) ) )
233 199 231 218 220 232 syl112anc
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( 2 x. ( Re ` A ) ) < _pi <-> ( Re ` A ) < ( _pi / 2 ) ) )
234 189 233 mpbird
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( 2 x. ( Re ` A ) ) < _pi )
235 230 231 234 ltled
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( 2 x. ( Re ` A ) ) <_ _pi )
236 227 235 eqbrtrd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( Im ` ( 2 x. ( _i x. A ) ) ) <_ _pi )
237 ellogrn
 |-  ( ( 2 x. ( _i x. A ) ) e. ran log <-> ( ( 2 x. ( _i x. A ) ) e. CC /\ -u _pi < ( Im ` ( 2 x. ( _i x. A ) ) ) /\ ( Im ` ( 2 x. ( _i x. A ) ) ) <_ _pi ) )
238 208 228 236 237 syl3anbrc
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( 2 x. ( _i x. A ) ) e. ran log )
239 logef
 |-  ( ( 2 x. ( _i x. A ) ) e. ran log -> ( log ` ( exp ` ( 2 x. ( _i x. A ) ) ) ) = ( 2 x. ( _i x. A ) ) )
240 238 239 syl
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( log ` ( exp ` ( 2 x. ( _i x. A ) ) ) ) = ( 2 x. ( _i x. A ) ) )
241 93 205 240 3eqtr3d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) = ( 2 x. ( _i x. A ) ) )
242 241 negeqd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> -u ( ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) ) = -u ( 2 x. ( _i x. A ) ) )
243 22 242 eqtr3d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) ) = -u ( 2 x. ( _i x. A ) ) )
244 243 oveq2d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( _i / 2 ) x. ( ( log ` ( 1 - ( _i x. ( tan ` A ) ) ) ) - ( log ` ( 1 + ( _i x. ( tan ` A ) ) ) ) ) ) = ( ( _i / 2 ) x. -u ( 2 x. ( _i x. A ) ) ) )
245 halfcl
 |-  ( _i e. CC -> ( _i / 2 ) e. CC )
246 7 245 mp1i
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( _i / 2 ) e. CC )
247 206 a1i
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> 2 e. CC )
248 246 247 79 mulassd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( ( _i / 2 ) x. 2 ) x. -u ( _i x. A ) ) = ( ( _i / 2 ) x. ( 2 x. -u ( _i x. A ) ) ) )
249 7 206 210 divcan1i
 |-  ( ( _i / 2 ) x. 2 ) = _i
250 249 oveq1i
 |-  ( ( ( _i / 2 ) x. 2 ) x. -u ( _i x. A ) ) = ( _i x. -u ( _i x. A ) )
251 33 33 51 mulassd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( _i x. _i ) x. -u A ) = ( _i x. ( _i x. -u A ) ) )
252 138 oveq1i
 |-  ( ( _i x. _i ) x. -u A ) = ( -u 1 x. -u A )
253 mul2neg
 |-  ( ( 1 e. CC /\ A e. CC ) -> ( -u 1 x. -u A ) = ( 1 x. A ) )
254 6 64 253 sylancr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( -u 1 x. -u A ) = ( 1 x. A ) )
255 mulid2
 |-  ( A e. CC -> ( 1 x. A ) = A )
256 255 adantr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( 1 x. A ) = A )
257 254 256 eqtrd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( -u 1 x. -u A ) = A )
258 252 257 syl5eq
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( _i x. _i ) x. -u A ) = A )
259 66 oveq2d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( _i x. ( _i x. -u A ) ) = ( _i x. -u ( _i x. A ) ) )
260 251 258 259 3eqtr3rd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( _i x. -u ( _i x. A ) ) = A )
261 250 260 syl5eq
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( ( _i / 2 ) x. 2 ) x. -u ( _i x. A ) ) = A )
262 mulneg2
 |-  ( ( 2 e. CC /\ ( _i x. A ) e. CC ) -> ( 2 x. -u ( _i x. A ) ) = -u ( 2 x. ( _i x. A ) ) )
263 206 76 262 sylancr
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( 2 x. -u ( _i x. A ) ) = -u ( 2 x. ( _i x. A ) ) )
264 263 oveq2d
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( _i / 2 ) x. ( 2 x. -u ( _i x. A ) ) ) = ( ( _i / 2 ) x. -u ( 2 x. ( _i x. A ) ) ) )
265 248 261 264 3eqtr3rd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( ( _i / 2 ) x. -u ( 2 x. ( _i x. A ) ) ) = A )
266 5 244 265 3eqtrd
 |-  ( ( A e. CC /\ ( Re ` A ) e. ( -u ( _pi / 2 ) (,) ( _pi / 2 ) ) ) -> ( arctan ` ( tan ` A ) ) = A )