Metamath Proof Explorer


Theorem mapfvd

Description: The value of a function that maps from B to A . (Contributed by AV, 2-Feb-2023)

Ref Expression
Hypotheses mapfvd.m ⊢ 𝑀 = ( 𝐴 ↑m 𝐵 )
mapfvd.f ⊢ ( 𝜑 → 𝐹 ∈ 𝑀 )
mapfvd.x ⊢ ( 𝜑 → 𝑋 ∈ 𝐵 )
Assertion mapfvd ( 𝜑 → ( 𝐹 ‘ 𝑋 ) ∈ 𝐴 )

Proof

Step Hyp Ref Expression
1 mapfvd.m ⊢ 𝑀 = ( 𝐴 ↑m 𝐵 )
2 mapfvd.f ⊢ ( 𝜑 → 𝐹 ∈ 𝑀 )
3 mapfvd.x ⊢ ( 𝜑 → 𝑋 ∈ 𝐵 )
4 elmapi ⊢ ( 𝐹 ∈ ( 𝐴 ↑m 𝐵 ) → 𝐹 : 𝐵 ⟶ 𝐴 )
5 ffvelcdm ⊢ ( ( 𝐹 : 𝐵 ⟶ 𝐴 ∧ 𝑋 ∈ 𝐵 ) → ( 𝐹 ‘ 𝑋 ) ∈ 𝐴 )
6 5 expcom ⊢ ( 𝑋 ∈ 𝐵 → ( 𝐹 : 𝐵 ⟶ 𝐴 → ( 𝐹 ‘ 𝑋 ) ∈ 𝐴 ) )
7 3 4 6 syl2imc ⊢ ( 𝐹 ∈ ( 𝐴 ↑m 𝐵 ) → ( 𝜑 → ( 𝐹 ‘ 𝑋 ) ∈ 𝐴 ) )
8 7 1 eleq2s ⊢ ( 𝐹 ∈ 𝑀 → ( 𝜑 → ( 𝐹 ‘ 𝑋 ) ∈ 𝐴 ) )
9 2 8 mpcom ⊢ ( 𝜑 → ( 𝐹 ‘ 𝑋 ) ∈ 𝐴 )