Metamath Proof Explorer


Theorem 1m0e1

Description: 1 - 0 = 1. (Contributed by David A. Wheeler, 8-Dec-2018)

Ref Expression
Assertion 1m0e1 1 0 = 1

Proof

Step Hyp Ref Expression
1 ax-1cn 1
2 1 subid1i 1 0 = 1