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Description: Deduction form of dffn5 . (Contributed by Mario Carneiro, 8-Jan-2015)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | feqmptd.1 | ⊢ ( 𝜑 → 𝐹 : 𝐴 ⟶ 𝐵 ) | |
| Assertion | feqmptd | ⊢ ( 𝜑 → 𝐹 = ( 𝑥 ∈ 𝐴 ↦ ( 𝐹 ‘ 𝑥 ) ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | feqmptd.1 | ⊢ ( 𝜑 → 𝐹 : 𝐴 ⟶ 𝐵 ) | |
| 2 | 1 | ffnd | ⊢ ( 𝜑 → 𝐹 Fn 𝐴 ) |
| 3 | dffn5 | ⊢ ( 𝐹 Fn 𝐴 ↔ 𝐹 = ( 𝑥 ∈ 𝐴 ↦ ( 𝐹 ‘ 𝑥 ) ) ) | |
| 4 | 2 3 | sylib | ⊢ ( 𝜑 → 𝐹 = ( 𝑥 ∈ 𝐴 ↦ ( 𝐹 ‘ 𝑥 ) ) ) |