Theorem fneq2 5470

Description: Equality theorem for function predicate with domain. (Contributed by NM, 1-Aug-1994.)

Assertion

Ref	Expression
fneq2	|- ( A = B -> ( F Fn A <-> F Fn B ) )

Proof of Theorem fneq2

Step	Hyp	Ref	Expression
1		eqeq2 2248	. . 3 |- ( A = B -> ( dom F = A <-> dom F = B ) )
2	1	anbi2d 468	. 2 |- ( A = B -> ( ( Fun F /\ dom F = A ) <-> ( Fun F /\ dom F = B ) ) )
3		df-fn 5380	. 2 |- ( F Fn A <-> ( Fun F /\ dom F = A ) )
4		df-fn 5380	. 2 |- ( F Fn B <-> ( Fun F /\ dom F = B ) )
5	2, 3, 4	3bitr4g 223	1 |- ( A = B -> ( F Fn A <-> F Fn B ) )

This proof depends on syntax axioms:   -> wi 4   /\ wa 104   <-> wb 105   = wceq 1402   dom cdm 4774   Fun wfun 5371   Fn wfn 5372

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-5 1500  ax-gen 1502  ax-4 1563  ax-17 1579  ax-ext 2220

This proof depends on definitions:  df-bi 117  df-cleq 2231  df-fn 5380

This theorem is used by:  fneq2d  5472  fneq2i  5476  feq2  5517  foeq2  5612  f1o00  5676  eqfnfv2  5807  tfr0dm  6593  tfrlemisucaccv  6596  tfrlemi1  6603  tfrlemi14d  6604  tfrexlem  6605  tfr1onlemsucfn  6611  tfr1onlemsucaccv  6612  tfr1onlembxssdm  6614  tfr1onlembfn  6615  tfr1onlemaccex  6619  tfr1onlemres  6620  ixpeq1  6991  0fz1  10449