Theorem feq3d 5261

Description: Equality deduction for functions. (Contributed by AV, 1-Jan-2020.)

Hypothesis

Ref	Expression
feq2d.1	|- ( ph -> A = B )

Assertion

Ref	Expression
feq3d	|- ( ph -> ( F : X --> A <-> F : X --> B ) )

Proof of Theorem feq3d

Step	Hyp	Ref	Expression
1		feq2d.1	. 2 |- ( ph -> A = B )
2		feq3 5257	. 2 |- ( A = B -> ( F : X --> A <-> F : X --> B ) )
3	1, 2	syl 14	1 |- ( ph -> ( F : X --> A <-> F : X --> B ) )

Syntax hints:   -> wi 4   <-> wb 104   = wceq 1331   -->wf 5119

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 1423  ax-7 1424  ax-gen 1425  ax-ie1 1469  ax-ie2 1470  ax-8 1482  ax-11 1484  ax-4 1487  ax-17 1506  ax-i9 1510  ax-ial 1514  ax-i5r 1515  ax-ext 2121

This theorem depends on definitions:  df-bi 116  df-nf 1437  df-sb 1736  df-clab 2126  df-cleq 2132  df-clel 2135  df-in 3077  df-ss 3084  df-f 5127

This theorem is referenced by:  uptx  12446  txcn  12447