Metamath Proof Explorer


Theorem xpeq2i

Description: Equality inference for Cartesian product. (Contributed by NM, 21-Dec-2008)

Ref Expression
Hypothesis xpeq1i.1 𝐴 = 𝐵
Assertion xpeq2i ( 𝐶 × 𝐴 ) = ( 𝐶 × 𝐵 )

Proof

Step Hyp Ref Expression
1 xpeq1i.1 𝐴 = 𝐵
2 xpeq2 ( 𝐴 = 𝐵 → ( 𝐶 × 𝐴 ) = ( 𝐶 × 𝐵 ) )
3 1 2 ax-mp ( 𝐶 × 𝐴 ) = ( 𝐶 × 𝐵 )