Theorem feq2 5331

Description: Equality theorem for functions. (Contributed by NM, 1-Aug-1994.)

Assertion

Ref	Expression
feq2	|- ( A = B -> ( F : A --> C <-> F : B --> C ) )

Proof of Theorem feq2

Step	Hyp	Ref	Expression
1		fneq2 5287	. . 3 |- ( A = B -> ( F Fn A <-> F Fn B ) )
2	1	anbi1d 462	. 2 |- ( A = B -> ( ( F Fn A /\ ran F C_ C ) <-> ( F Fn B /\ ran F C_ C ) ) )
3		df-f 5202	. 2 |- ( F : A --> C <-> ( F Fn A /\ ran F C_ C ) )
4		df-f 5202	. 2 |- ( F : B --> C <-> ( F Fn B /\ ran F C_ C ) )
5	2, 3, 4	3bitr4g 222	1 |- ( A = B -> ( F : A --> C <-> F : B --> C ) )

Syntax hints:   -> wi 4   /\ wa 103   <-> wb 104   = wceq 1348   C_ wss 3121   ran crn 4612   Fn wfn 5193   -->wf 5194

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-5 1440  ax-gen 1442  ax-4 1503  ax-17 1519  ax-ext 2152

This theorem depends on definitions:  df-bi 116  df-cleq 2163  df-fn 5201  df-f 5202

This theorem is referenced by:  feq23  5333  feq2d  5335  feq2i  5341  f00  5389  f0dom0  5391  f1eq2  5399  fressnfv  5683  tfrcllemsucfn  6332  tfrcllemsucaccv  6333  tfrcllembxssdm  6335  tfrcllembfn  6336  tfrcllemaccex  6340  tfrcllemres  6341  tfrcldm  6342  tfrcl  6343  mapvalg  6636  map0g  6666  ac6sfi  6876  isomni  7112  ismkv  7129  iswomni  7141