Description: Equality deduction for function value. (Contributed by BJ, 31-Aug-2022)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | fveqeq2 | |- ( A = B -> ( ( F ` A ) = C <-> ( F ` B ) = C ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | id | |- ( A = B -> A = B ) |
|
| 2 | 1 | fveqeq2d | |- ( A = B -> ( ( F ` A ) = C <-> ( F ` B ) = C ) ) |