Theorem imaeq2d

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

	Ref	Expression
Hypothesis	imaeq1d.1	|- ( ph -> A = B )
Assertion	imaeq2d	|- ( ph -> ( C " A ) = ( C " B ) )

Proof

Step	Hyp	Ref	Expression
1		imaeq1d.1	|- ( ph -> A = B )
2		imaeq2	|- ( A = B -> ( C " A ) = ( C " B ) )
3	1 2	syl	|- ( ph -> ( C " A ) = ( C " B ) )