Metamath Proof Explorer


Theorem imaeq1d

Description: Equality theorem for image. (Contributed by FL, 15-Dec-2006)

Ref Expression
Hypothesis imaeq1d.1
|- ( ph -> A = B )
Assertion imaeq1d
|- ( ph -> ( A " C ) = ( B " C ) )

Proof

Step Hyp Ref Expression
1 imaeq1d.1
 |-  ( ph -> A = B )
2 imaeq1
 |-  ( A = B -> ( A " C ) = ( B " C ) )
3 1 2 syl
 |-  ( ph -> ( A " C ) = ( B " C ) )