Metamath Proof Explorer


Theorem xrltned

Description: 'Less than' implies not equal. (Contributed by Glauco Siliprandi, 21-Nov-2020)

Ref Expression
Hypotheses xrltned.1 φA*
xrltned.2 φB*
xrltned.3 φA<B
Assertion xrltned φAB

Proof

Step Hyp Ref Expression
1 xrltned.1 φA*
2 xrltned.2 φB*
3 xrltned.3 φA<B
4 1 2 3 xrgtned φBA
5 4 necomd φAB