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 ) ) |
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 ) ) |