Metamath Proof Explorer


Theorem div1d

Description: A number divided by 1 is itself. (Contributed by Mario Carneiro, 27-May-2016)

Ref Expression
Hypothesis div1d.1 φA
Assertion div1d φA1=A

Proof

Step Hyp Ref Expression
1 div1d.1 φA
2 div1 AA1=A
3 1 2 syl φA1=A