Metamath Proof Explorer


Theorem 1ne2

Description: 1 is not equal to 2. (Contributed by NM, 19-Oct-2012)

Ref Expression
Assertion 1ne2 1 2

Proof

Step Hyp Ref Expression
1 1re 1
2 1lt2 1 < 2
3 1 2 ltneii 1 2