Metamath Proof Explorer


Theorem eqnetrri

Description: Substitution of equal classes into an inequality. (Contributed by NM, 4-Jul-2012)

Ref Expression
Hypotheses eqnetrr.1
|- A = B
eqnetrr.2
|- A =/= C
Assertion eqnetrri
|- B =/= C

Proof

Step Hyp Ref Expression
1 eqnetrr.1
 |-  A = B
2 eqnetrr.2
 |-  A =/= C
3 1 eqcomi
 |-  B = A
4 3 2 eqnetri
 |-  B =/= C