Description: The second element in an ordered pair member of a function is the function's value. (Contributed by NM, 19-Jul-1996)
Ref | Expression | ||
---|---|---|---|
Assertion | funopfv | ⊢ ( Fun 𝐹 → ( 〈 𝐴 , 𝐵 〉 ∈ 𝐹 → ( 𝐹 ‘ 𝐴 ) = 𝐵 ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-br | ⊢ ( 𝐴 𝐹 𝐵 ↔ 〈 𝐴 , 𝐵 〉 ∈ 𝐹 ) | |
2 | funbrfv | ⊢ ( Fun 𝐹 → ( 𝐴 𝐹 𝐵 → ( 𝐹 ‘ 𝐴 ) = 𝐵 ) ) | |
3 | 1 2 | syl5bir | ⊢ ( Fun 𝐹 → ( 〈 𝐴 , 𝐵 〉 ∈ 𝐹 → ( 𝐹 ‘ 𝐴 ) = 𝐵 ) ) |