Metamath Proof Explorer


Theorem mulridd

Description: Identity law for multiplication. (Contributed by Mario Carneiro, 27-May-2016)

Ref Expression
Hypothesis addcld.1 φ A
Assertion mulridd φ A 1 = A

Proof

Step Hyp Ref Expression
1 addcld.1 φ A
2 mulrid A A 1 = A
3 1 2 syl φ A 1 = A