Metamath Proof Explorer


Theorem dp2eq2i

Description: Equality theorem for the decimal expansion constructor. (Contributed by David A. Wheeler, 15-May-2015)

Ref Expression
Hypothesis dp2eq1i.1 𝐴 = 𝐵
Assertion dp2eq2i 𝐶 𝐴 = 𝐶 𝐵

Proof

Step Hyp Ref Expression
1 dp2eq1i.1 𝐴 = 𝐵
2 dp2eq2 ( 𝐴 = 𝐵 𝐶 𝐴 = 𝐶 𝐵 )
3 1 2 ax-mp 𝐶 𝐴 = 𝐶 𝐵