Description: Equality deduction for the function predicate. (Contributed by NM, 23-Feb-2013)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | funeqd.1 | ⊢ ( 𝜑 → 𝐴 = 𝐵 ) | |
| Assertion | funeqd | ⊢ ( 𝜑 → ( Fun 𝐴 ↔ Fun 𝐵 ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | funeqd.1 | ⊢ ( 𝜑 → 𝐴 = 𝐵 ) | |
| 2 | funeq | ⊢ ( 𝐴 = 𝐵 → ( Fun 𝐴 ↔ Fun 𝐵 ) ) | |
| 3 | 1 2 | syl | ⊢ ( 𝜑 → ( Fun 𝐴 ↔ Fun 𝐵 ) ) |