Metamath Proof Explorer


Theorem imaeq2i

Description: Equality theorem for image. (Contributed by NM, 21-Dec-2008)

Ref Expression
Hypothesis imaeq1i.1 A=B
Assertion imaeq2i CA=CB

Proof

Step Hyp Ref Expression
1 imaeq1i.1 A=B
2 imaeq2 A=BCA=CB
3 1 2 ax-mp CA=CB