Theorem efival 12418

Description: The exponential function in terms of sine and cosine. (Contributed by NM, 30-Apr-2005.)

Assertion

Ref	Expression
efival	|- ( A e. CC -> ( exp ` ( _i x. A ) ) = ( ( cos ` A ) + ( _i x. ( sin ` A ) ) ) )

Proof of Theorem efival

Step	Hyp	Ref	Expression
1		ax-icn 8222	. . . . . 6 |- _i e. CC
2		mulcl 8254	. . . . . 6 |- ( ( _i e. CC /\ A e. CC ) -> ( _i x. A ) e. CC )
3	1, 2	mpan 424	. . . . 5 |- ( A e. CC -> ( _i x. A ) e. CC )
4		efcl 12350	. . . . 5 |- ( ( _i x. A ) e. CC -> ( exp ` ( _i x. A ) ) e. CC )
5	3, 4	syl 14	. . . 4 |- ( A e. CC -> ( exp ` ( _i x. A ) ) e. CC )
6		negicn 8474	. . . . . 6 |- -u _i e. CC
7		mulcl 8254	. . . . . 6 |- ( ( -u _i e. CC /\ A e. CC ) -> ( -u _i x. A ) e. CC )
8	6, 7	mpan 424	. . . . 5 |- ( A e. CC -> ( -u _i x. A ) e. CC )
9		efcl 12350	. . . . 5 |- ( ( -u _i x. A ) e. CC -> ( exp ` ( -u _i x. A ) ) e. CC )
10	8, 9	syl 14	. . . 4 |- ( A e. CC -> ( exp ` ( -u _i x. A ) ) e. CC )
11	5, 10	addcld 8293	. . 3 |- ( A e. CC -> ( ( exp ` ( _i x. A ) ) + ( exp ` ( -u _i x. A ) ) ) e. CC )
12	5, 10	subcld 8584	. . 3 |- ( A e. CC -> ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) e. CC )
13		2cn 9308	. . . . 5 |- 2 e. CC
14		2ap0 9330	. . . . 5 |- 2 # 0
15	13, 14	pm3.2i 272	. . . 4 |- ( 2 e. CC /\ 2 # 0 )
16		divdirap 8971	. . . 4 |- ( ( ( ( exp ` ( _i x. A ) ) + ( exp ` ( -u _i x. A ) ) ) e. CC /\ ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) e. CC /\ ( 2 e. CC /\ 2 # 0 ) ) -> ( ( ( ( exp ` ( _i x. A ) ) + ( exp ` ( -u _i x. A ) ) ) + ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) ) / 2 ) = ( ( ( ( exp ` ( _i x. A ) ) + ( exp ` ( -u _i x. A ) ) ) / 2 ) + ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) / 2 ) ) )
17	15, 16	mp3an3 1363	. . 3 |- ( ( ( ( exp ` ( _i x. A ) ) + ( exp ` ( -u _i x. A ) ) ) e. CC /\ ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) e. CC ) -> ( ( ( ( exp ` ( _i x. A ) ) + ( exp ` ( -u _i x. A ) ) ) + ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) ) / 2 ) = ( ( ( ( exp ` ( _i x. A ) ) + ( exp ` ( -u _i x. A ) ) ) / 2 ) + ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) / 2 ) ) )
18	11, 12, 17	syl2anc 411	. 2 |- ( A e. CC -> ( ( ( ( exp ` ( _i x. A ) ) + ( exp ` ( -u _i x. A ) ) ) + ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) ) / 2 ) = ( ( ( ( exp ` ( _i x. A ) ) + ( exp ` ( -u _i x. A ) ) ) / 2 ) + ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) / 2 ) ) )
19	10, 5	pncan3d 8587	. . . . . 6 |- ( A e. CC -> ( ( exp ` ( -u _i x. A ) ) + ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) ) = ( exp ` ( _i x. A ) ) )
20	19	oveq2d 6066	. . . . 5 |- ( A e. CC -> ( ( exp ` ( _i x. A ) ) + ( ( exp ` ( -u _i x. A ) ) + ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) ) ) = ( ( exp ` ( _i x. A ) ) + ( exp ` ( _i x. A ) ) ) )
21	5, 10, 12	addassd 8296	. . . . 5 |- ( A e. CC -> ( ( ( exp ` ( _i x. A ) ) + ( exp ` ( -u _i x. A ) ) ) + ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) ) = ( ( exp ` ( _i x. A ) ) + ( ( exp ` ( -u _i x. A ) ) + ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) ) ) )
22	5	2timesd 9481	. . . . 5 |- ( A e. CC -> ( 2 x. ( exp ` ( _i x. A ) ) ) = ( ( exp ` ( _i x. A ) ) + ( exp ` ( _i x. A ) ) ) )
23	20, 21, 22	3eqtr4d 2275	. . . 4 |- ( A e. CC -> ( ( ( exp ` ( _i x. A ) ) + ( exp ` ( -u _i x. A ) ) ) + ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) ) = ( 2 x. ( exp ` ( _i x. A ) ) ) )
24	23	oveq1d 6065	. . 3 |- ( A e. CC -> ( ( ( ( exp ` ( _i x. A ) ) + ( exp ` ( -u _i x. A ) ) ) + ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) ) / 2 ) = ( ( 2 x. ( exp ` ( _i x. A ) ) ) / 2 ) )
25		divcanap3 8972	. . . . 5 |- ( ( ( exp ` ( _i x. A ) ) e. CC /\ 2 e. CC /\ 2 # 0 ) -> ( ( 2 x. ( exp ` ( _i x. A ) ) ) / 2 ) = ( exp ` ( _i x. A ) ) )
26	13, 14, 25	mp3an23 1366	. . . 4 |- ( ( exp ` ( _i x. A ) ) e. CC -> ( ( 2 x. ( exp ` ( _i x. A ) ) ) / 2 ) = ( exp ` ( _i x. A ) ) )
27	5, 26	syl 14	. . 3 |- ( A e. CC -> ( ( 2 x. ( exp ` ( _i x. A ) ) ) / 2 ) = ( exp ` ( _i x. A ) ) )
28	24, 27	eqtr2d 2266	. 2 |- ( A e. CC -> ( exp ` ( _i x. A ) ) = ( ( ( ( exp ` ( _i x. A ) ) + ( exp ` ( -u _i x. A ) ) ) + ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) ) / 2 ) )
29		cosval 12389	. . 3 |- ( A e. CC -> ( cos ` A ) = ( ( ( exp ` ( _i x. A ) ) + ( exp ` ( -u _i x. A ) ) ) / 2 ) )
30		2mulicn 9460	. . . . . . 7 |- ( 2 x. _i ) e. CC
31		2muliap0 9462	. . . . . . 7 |- ( 2 x. _i ) # 0
32	30, 31	pm3.2i 272	. . . . . 6 |- ( ( 2 x. _i ) e. CC /\ ( 2 x. _i ) # 0 )
33		div12ap 8968	. . . . . 6 |- ( ( _i e. CC /\ ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) e. CC /\ ( ( 2 x. _i ) e. CC /\ ( 2 x. _i ) # 0 ) ) -> ( _i x. ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) / ( 2 x. _i ) ) ) = ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) x. ( _i / ( 2 x. _i ) ) ) )
34	1, 32, 33	mp3an13 1365	. . . . 5 |- ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) e. CC -> ( _i x. ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) / ( 2 x. _i ) ) ) = ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) x. ( _i / ( 2 x. _i ) ) ) )
35	12, 34	syl 14	. . . 4 |- ( A e. CC -> ( _i x. ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) / ( 2 x. _i ) ) ) = ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) x. ( _i / ( 2 x. _i ) ) ) )
36		sinval 12388	. . . . 5 |- ( A e. CC -> ( sin ` A ) = ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) / ( 2 x. _i ) ) )
37	36	oveq2d 6066	. . . 4 |- ( A e. CC -> ( _i x. ( sin ` A ) ) = ( _i x. ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) / ( 2 x. _i ) ) ) )
38		divrecap 8962	. . . . . . 7 |- ( ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) e. CC /\ 2 e. CC /\ 2 # 0 ) -> ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) / 2 ) = ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) x. ( 1 / 2 ) ) )
39	13, 14, 38	mp3an23 1366	. . . . . 6 |- ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) e. CC -> ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) / 2 ) = ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) x. ( 1 / 2 ) ) )
40	12, 39	syl 14	. . . . 5 |- ( A e. CC -> ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) / 2 ) = ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) x. ( 1 / 2 ) ) )
41	1	mullidi 8277	. . . . . . . 8 |- ( 1 x. _i ) = _i
42	41	oveq1i 6060	. . . . . . 7 |- ( ( 1 x. _i ) / ( 2 x. _i ) ) = ( _i / ( 2 x. _i ) )
43		iap0 9461	. . . . . . . . . . 11 |- _i # 0
44	1, 43	dividapi 9019	. . . . . . . . . 10 |- ( _i / _i ) = 1
45	44	oveq2i 6061	. . . . . . . . 9 |- ( ( 1 / 2 ) x. ( _i / _i ) ) = ( ( 1 / 2 ) x. 1 )
46		ax-1cn 8220	. . . . . . . . . 10 |- 1 e. CC
47	46, 13, 1, 1, 14, 43	divmuldivapi 9046	. . . . . . . . 9 |- ( ( 1 / 2 ) x. ( _i / _i ) ) = ( ( 1 x. _i ) / ( 2 x. _i ) )
48	45, 47	eqtr3i 2255	. . . . . . . 8 |- ( ( 1 / 2 ) x. 1 ) = ( ( 1 x. _i ) / ( 2 x. _i ) )
49		halfcn 9452	. . . . . . . . 9 |- ( 1 / 2 ) e. CC
50	49	mulridi 8276	. . . . . . . 8 |- ( ( 1 / 2 ) x. 1 ) = ( 1 / 2 )
51	48, 50	eqtr3i 2255	. . . . . . 7 |- ( ( 1 x. _i ) / ( 2 x. _i ) ) = ( 1 / 2 )
52	42, 51	eqtr3i 2255	. . . . . 6 |- ( _i / ( 2 x. _i ) ) = ( 1 / 2 )
53	52	oveq2i 6061	. . . . 5 |- ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) x. ( _i / ( 2 x. _i ) ) ) = ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) x. ( 1 / 2 ) )
54	40, 53	eqtr4di 2283	. . . 4 |- ( A e. CC -> ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) / 2 ) = ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) x. ( _i / ( 2 x. _i ) ) ) )
55	35, 37, 54	3eqtr4d 2275	. . 3 |- ( A e. CC -> ( _i x. ( sin ` A ) ) = ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) / 2 ) )
56	29, 55	oveq12d 6068	. 2 |- ( A e. CC -> ( ( cos ` A ) + ( _i x. ( sin ` A ) ) ) = ( ( ( ( exp ` ( _i x. A ) ) + ( exp ` ( -u _i x. A ) ) ) / 2 ) + ( ( ( exp ` ( _i x. A ) ) - ( exp ` ( -u _i x. A ) ) ) / 2 ) ) )
57	18, 28, 56	3eqtr4d 2275	1 |- ( A e. CC -> ( exp ` ( _i x. A ) ) = ( ( cos ` A ) + ( _i x. ( sin ` A ) ) ) )

Syntax hints:   -> wi 4   /\ wa 104   = wceq 1398   e. wcel 2203   class class class wbr 4109   ` cfv 5352  (class class class)co 6050   CCcc 8125   0cc0 8127   1c1 8128   _ici 8129   + caddc 8130   x. cmul 8132   - cmin 8444   -ucneg 8445   # cap 8855   / cdiv 8946   2c2 9288   expce 12328   sincsin 12330   cosccos 12331

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 619  ax-in2 620  ax-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-13 2205  ax-14 2206  ax-ext 2214  ax-coll 4225  ax-sep 4228  ax-nul 4236  ax-pow 4287  ax-pr 4322  ax-un 4554  ax-setind 4659  ax-iinf 4710  ax-cnex 8218  ax-resscn 8219  ax-1cn 8220  ax-1re 8221  ax-icn 8222  ax-addcl 8223  ax-addrcl 8224  ax-mulcl 8225  ax-mulrcl 8226  ax-addcom 8227  ax-mulcom 8228  ax-addass 8229  ax-mulass 8230  ax-distr 8231  ax-i2m1 8232  ax-0lt1 8233  ax-1rid 8234  ax-0id 8235  ax-rnegex 8236  ax-precex 8237  ax-cnre 8238  ax-pre-ltirr 8239  ax-pre-ltwlin 8240  ax-pre-lttrn 8241  ax-pre-apti 8242  ax-pre-ltadd 8243  ax-pre-mulgt0 8244  ax-pre-mulext 8245  ax-arch 8246  ax-caucvg 8247

This theorem depends on definitions:  df-bi 117  df-dc 843  df-3or 1006  df-3an 1007  df-tru 1401  df-fal 1404  df-nf 1510  df-sb 1812  df-eu 2083  df-mo 2084  df-clab 2219  df-cleq 2225  df-clel 2228  df-nfc 2373  df-ne 2413  df-nel 2508  df-ral 2525  df-rex 2526  df-reu 2527  df-rmo 2528  df-rab 2529  df-v 2815  df-sbc 3043  df-csb 3139  df-dif 3213  df-un 3215  df-in 3217  df-ss 3224  df-nul 3509  df-if 3621  df-pw 3671  df-sn 3695  df-pr 3696  df-op 3698  df-uni 3915  df-int 3950  df-iun 3993  df-br 4110  df-opab 4172  df-mpt 4173  df-tr 4209  df-id 4414  df-po 4417  df-iso 4418  df-iord 4487  df-on 4489  df-ilim 4490  df-suc 4492  df-iom 4713  df-xp 4755  df-rel 4756  df-cnv 4757  df-co 4758  df-dm 4759  df-rn 4760  df-res 4761  df-ima 4762  df-iota 5312  df-fun 5354  df-fn 5355  df-f 5356  df-f1 5357  df-fo 5358  df-f1o 5359  df-fv 5360  df-isom 5361  df-riota 6003  df-ov 6053  df-oprab 6054  df-mpo 6055  df-1st 6334  df-2nd 6335  df-recs 6536  df-irdg 6601  df-frec 6622  df-1o 6647  df-oadd 6651  df-er 6767  df-en 6976  df-dom 6977  df-fin 6978  df-pnf 8310  df-mnf 8311  df-xr 8312  df-ltxr 8313  df-le 8314  df-sub 8446  df-neg 8447  df-reap 8849  df-ap 8856  df-div 8947  df-inn 9238  df-2 9296  df-3 9297  df-4 9298  df-n0 9497  df-z 9578  df-uz 9854  df-q 9952  df-rp 9987  df-ico 10227  df-fz 10343  df-fzo 10477  df-seqfrec 10810  df-exp 10901  df-fac 11088  df-ihash 11139  df-cj 11527  df-re 11528  df-im 11529  df-rsqrt 11683  df-abs 11684  df-clim 11964  df-sumdc 12039  df-ef 12334  df-sin 12336  df-cos 12337

This theorem is referenced by:  efmival  12419  efeul  12420  efieq  12421  sinadd  12422  cosadd  12423  absefi  12455  demoivre  12459  efhalfpi  15664  efipi  15666  ef2pi  15670  efimpi  15684