Description: Equality theorem for the range Cartesian product. (Contributed by Peter Mazsa, 16-Dec-2020)
Ref | Expression | ||
---|---|---|---|
Assertion | xrneq1 | ⊢ ( 𝐴 = 𝐵 → ( 𝐴 ⋉ 𝐶 ) = ( 𝐵 ⋉ 𝐶 ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | coeq2 | ⊢ ( 𝐴 = 𝐵 → ( ◡ ( 1st ↾ ( V × V ) ) ∘ 𝐴 ) = ( ◡ ( 1st ↾ ( V × V ) ) ∘ 𝐵 ) ) | |
2 | 1 | ineq1d | ⊢ ( 𝐴 = 𝐵 → ( ( ◡ ( 1st ↾ ( V × V ) ) ∘ 𝐴 ) ∩ ( ◡ ( 2nd ↾ ( V × V ) ) ∘ 𝐶 ) ) = ( ( ◡ ( 1st ↾ ( V × V ) ) ∘ 𝐵 ) ∩ ( ◡ ( 2nd ↾ ( V × V ) ) ∘ 𝐶 ) ) ) |
3 | df-xrn | ⊢ ( 𝐴 ⋉ 𝐶 ) = ( ( ◡ ( 1st ↾ ( V × V ) ) ∘ 𝐴 ) ∩ ( ◡ ( 2nd ↾ ( V × V ) ) ∘ 𝐶 ) ) | |
4 | df-xrn | ⊢ ( 𝐵 ⋉ 𝐶 ) = ( ( ◡ ( 1st ↾ ( V × V ) ) ∘ 𝐵 ) ∩ ( ◡ ( 2nd ↾ ( V × V ) ) ∘ 𝐶 ) ) | |
5 | 2 3 4 | 3eqtr4g | ⊢ ( 𝐴 = 𝐵 → ( 𝐴 ⋉ 𝐶 ) = ( 𝐵 ⋉ 𝐶 ) ) |