Theorem feq2 5411

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 5364	. . 3 |- ( A = B -> ( F Fn A <-> F Fn B ) )
2	1	anbi1d 465	. 2 |- ( A = B -> ( ( F Fn A /\ ran F C_ C ) <-> ( F Fn B /\ ran F C_ C ) ) )
3		df-f 5276	. 2 |- ( F : A --> C <-> ( F Fn A /\ ran F C_ C ) )
4		df-f 5276	. 2 |- ( F : B --> C <-> ( F Fn B /\ ran F C_ C ) )
5	2, 3, 4	3bitr4g 223	1 |- ( A = B -> ( F : A --> C <-> F : B --> C ) )

Syntax hints:   -> wi 4   /\ wa 104   <-> wb 105   = wceq 1373   C_ wss 3166   ran crn 4677   Fn wfn 5267   -->wf 5268

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-5 1470  ax-gen 1472  ax-4 1533  ax-17 1549  ax-ext 2187

This theorem depends on definitions:  df-bi 117  df-cleq 2198  df-fn 5275  df-f 5276

This theorem is referenced by:  feq23  5413  feq2d  5415  feq2i  5421  f00  5469  f0dom0  5471  f1eq2  5479  fressnfv  5773  tfrcllemsucfn  6441  tfrcllemsucaccv  6442  tfrcllembxssdm  6444  tfrcllembfn  6445  tfrcllemaccex  6449  tfrcllemres  6450  tfrcldm  6451  tfrcl  6452  mapvalg  6747  map0g  6777  ac6sfi  6997  isomni  7240  ismkv  7257  iswomni  7269  isghm  13612