Metamath Proof Explorer


Theorem f1oeq2d

Description: Equality deduction for one-to-one onto functions. (Contributed by Glauco Siliprandi, 17-Aug-2020)

Ref Expression
Hypothesis f1oeq2d.1
|- ( ph -> A = B )
Assertion f1oeq2d
|- ( ph -> ( F : A -1-1-onto-> C <-> F : B -1-1-onto-> C ) )

Proof

Step Hyp Ref Expression
1 f1oeq2d.1
 |-  ( ph -> A = B )
2 f1oeq2
 |-  ( A = B -> ( F : A -1-1-onto-> C <-> F : B -1-1-onto-> C ) )
3 1 2 syl
 |-  ( ph -> ( F : A -1-1-onto-> C <-> F : B -1-1-onto-> C ) )