Description: Equality theorem for image. (Contributed by NM, 21-Dec-2008)
Ref | Expression | ||
---|---|---|---|
Hypothesis | imaeq1i.1 | |- A = B |
|
Assertion | imaeq2i | |- ( C " A ) = ( C " B ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | imaeq1i.1 | |- A = B |
|
2 | imaeq2 | |- ( A = B -> ( C " A ) = ( C " B ) ) |
|
3 | 1 2 | ax-mp | |- ( C " A ) = ( C " B ) |