Theorem ofco 6917

Description: The composition of a function operation with another function. (Contributed by Mario Carneiro, 19-Dec-2014.)

Hypotheses

Ref	Expression
ofco.1	|- ( ph -> F Fn A )
ofco.2	|- ( ph -> G Fn B )
ofco.3	|- ( ph -> H : D --> C )
ofco.4	|- ( ph -> A e. V )
ofco.5	|- ( ph -> B e. W )
ofco.6	|- ( ph -> D e. X )
ofco.7	|- ( A i^i B ) = C

Assertion

Ref	Expression
ofco	|- ( ph -> ( ( F oF R G ) o. H ) = ( ( F o. H ) oF R ( G o. H ) ) )

Proof of Theorem ofco

Dummy variables y x are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		ofco.3	. . . 4 |- ( ph -> H : D --> C )
2	1	ffvelrnda 6359	. . 3 |- ( ( ph /\ x e. D ) -> ( H ` x ) e. C )
3	1	feqmptd 6249	. . 3 |- ( ph -> H = ( x e. D |-> ( H ` x ) ) )
4		ofco.1	. . . 4 |- ( ph -> F Fn A )
5		ofco.2	. . . 4 |- ( ph -> G Fn B )
6		ofco.4	. . . 4 |- ( ph -> A e. V )
7		ofco.5	. . . 4 |- ( ph -> B e. W )
8		ofco.7	. . . 4 |- ( A i^i B ) = C
9		eqidd 2623	. . . 4 |- ( ( ph /\ y e. A ) -> ( F ` y ) = ( F ` y ) )
10		eqidd 2623	. . . 4 |- ( ( ph /\ y e. B ) -> ( G ` y ) = ( G ` y ) )
11	4, 5, 6, 7, 8, 9, 10	offval 6904	. . 3 |- ( ph -> ( F oF R G ) = ( y e. C |-> ( ( F ` y ) R ( G ` y ) ) ) )
12		fveq2 6191	. . . 4 |- ( y = ( H ` x ) -> ( F ` y ) = ( F ` ( H ` x ) ) )
13		fveq2 6191	. . . 4 |- ( y = ( H ` x ) -> ( G ` y ) = ( G ` ( H ` x ) ) )
14	12, 13	oveq12d 6668	. . 3 |- ( y = ( H ` x ) -> ( ( F ` y ) R ( G ` y ) ) = ( ( F ` ( H ` x ) ) R ( G ` ( H ` x ) ) ) )
15	2, 3, 11, 14	fmptco 6396	. 2 |- ( ph -> ( ( F oF R G ) o. H ) = ( x e. D |-> ( ( F ` ( H ` x ) ) R ( G ` ( H ` x ) ) ) ) )
16		inss1 3833	. . . . . 6 |- ( A i^i B ) C_ A
17	8, 16	eqsstr3i 3636	. . . . 5 |- C C_ A
18		fss 6056	. . . . 5 |- ( ( H : D --> C /\ C C_ A ) -> H : D --> A )
19	1, 17, 18	sylancl 694	. . . 4 |- ( ph -> H : D --> A )
20		fnfco 6069	. . . 4 |- ( ( F Fn A /\ H : D --> A ) -> ( F o. H ) Fn D )
21	4, 19, 20	syl2anc 693	. . 3 |- ( ph -> ( F o. H ) Fn D )
22		inss2 3834	. . . . . 6 |- ( A i^i B ) C_ B
23	8, 22	eqsstr3i 3636	. . . . 5 |- C C_ B
24		fss 6056	. . . . 5 |- ( ( H : D --> C /\ C C_ B ) -> H : D --> B )
25	1, 23, 24	sylancl 694	. . . 4 |- ( ph -> H : D --> B )
26		fnfco 6069	. . . 4 |- ( ( G Fn B /\ H : D --> B ) -> ( G o. H ) Fn D )
27	5, 25, 26	syl2anc 693	. . 3 |- ( ph -> ( G o. H ) Fn D )
28		ofco.6	. . 3 |- ( ph -> D e. X )
29		inidm 3822	. . 3 |- ( D i^i D ) = D
30		ffn 6045	. . . . 5 |- ( H : D --> C -> H Fn D )
31	1, 30	syl 17	. . . 4 |- ( ph -> H Fn D )
32		fvco2 6273	. . . 4 |- ( ( H Fn D /\ x e. D ) -> ( ( F o. H ) ` x ) = ( F ` ( H ` x ) ) )
33	31, 32	sylan 488	. . 3 |- ( ( ph /\ x e. D ) -> ( ( F o. H ) ` x ) = ( F ` ( H ` x ) ) )
34		fvco2 6273	. . . 4 |- ( ( H Fn D /\ x e. D ) -> ( ( G o. H ) ` x ) = ( G ` ( H ` x ) ) )
35	31, 34	sylan 488	. . 3 |- ( ( ph /\ x e. D ) -> ( ( G o. H ) ` x ) = ( G ` ( H ` x ) ) )
36	21, 27, 28, 28, 29, 33, 35	offval 6904	. 2 |- ( ph -> ( ( F o. H ) oF R ( G o. H ) ) = ( x e. D |-> ( ( F ` ( H ` x ) ) R ( G ` ( H ` x ) ) ) ) )
37	15, 36	eqtr4d 2659	1 |- ( ph -> ( ( F oF R G ) o. H ) = ( ( F o. H ) oF R ( G o. H ) ) )

Syntax hints:   -> wi 4   /\ wa 384   = wceq 1483   e. wcel 1990   i^i cin 3573   C_ wss 3574   |-> cmpt 4729   o. ccom 5118   Fn wfn 5883   -->wf 5884   ` cfv 5888  (class class class)co 6650   oFcof 6895

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-8 1992  ax-9 1999  ax-10 2019  ax-11 2034  ax-12 2047  ax-13 2246  ax-ext 2602  ax-rep 4771  ax-sep 4781  ax-nul 4789  ax-pow 4843  ax-pr 4906

This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3an 1039  df-tru 1486  df-ex 1705  df-nf 1710  df-sb 1881  df-eu 2474  df-mo 2475  df-clab 2609  df-cleq 2615  df-clel 2618  df-nfc 2753  df-ne 2795  df-ral 2917  df-rex 2918  df-reu 2919  df-rab 2921  df-v 3202  df-sbc 3436  df-csb 3534  df-dif 3577  df-un 3579  df-in 3581  df-ss 3588  df-nul 3916  df-if 4087  df-sn 4178  df-pr 4180  df-op 4184  df-uni 4437  df-iun 4522  df-br 4654  df-opab 4713  df-mpt 4730  df-id 5024  df-xp 5120  df-rel 5121  df-cnv 5122  df-co 5123  df-dm 5124  df-rn 5125  df-res 5126  df-ima 5127  df-iota 5851  df-fun 5890  df-fn 5891  df-f 5892  df-f1 5893  df-fo 5894  df-f1o 5895  df-fv 5896  df-ov 6653  df-oprab 6654  df-mpt2 6655  df-of 6897

This theorem is referenced by:  gsumzaddlem  18321  coe1add  19634  pf1ind  19719  mendring  37762