Metamath Proof Explorer


Theorem mul02d

Description: Multiplication by 0. Theorem I.6 of Apostol p. 18. (Contributed by Mario Carneiro, 27-May-2016)

Ref Expression
Hypothesis muld.1 φA
Assertion mul02d φ0A=0

Proof

Step Hyp Ref Expression
1 muld.1 φA
2 mul02 A0A=0
3 1 2 syl φ0A=0