Metamath Proof Explorer


Theorem xrltned

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

Ref Expression
Hypotheses xrltned.1 φ A *
xrltned.2 φ B *
xrltned.3 φ A < B
Assertion xrltned φ A B

Proof

Step Hyp Ref Expression
1 xrltned.1 φ A *
2 xrltned.2 φ B *
3 xrltned.3 φ A < B
4 1 2 3 xrgtned φ B A
5 4 necomd φ A B