Description: Equality deduction for function value. (Contributed by NM, 2-Sep-2003)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | fveq1d.1 | ⊢ ( 𝜑 → 𝐹 = 𝐺 ) | |
| Assertion | fveq1d | ⊢ ( 𝜑 → ( 𝐹 ‘ 𝐴 ) = ( 𝐺 ‘ 𝐴 ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | fveq1d.1 | ⊢ ( 𝜑 → 𝐹 = 𝐺 ) | |
| 2 | fveq1 | ⊢ ( 𝐹 = 𝐺 → ( 𝐹 ‘ 𝐴 ) = ( 𝐺 ‘ 𝐴 ) ) | |
| 3 | 1 2 | syl | ⊢ ( 𝜑 → ( 𝐹 ‘ 𝐴 ) = ( 𝐺 ‘ 𝐴 ) ) |