Metamath Proof Explorer


Theorem gt-lth

Description: Relationship between < and > using hypotheses. (Contributed by David A. Wheeler, 19-Apr-2015) (New usage is discouraged.)

Ref Expression
Hypotheses gt-lth.1
|- A e. _V
gt-lth.2
|- B e. _V
Assertion gt-lth
|- ( A > B <-> B < A )

Proof

Step Hyp Ref Expression
1 gt-lth.1
 |-  A e. _V
2 gt-lth.2
 |-  B e. _V
3 df-gt
 |-  > = `' <
4 3 breqi
 |-  ( A > B <-> A `' < B )
5 1 2 brcnv
 |-  ( A `' < B <-> B < A )
6 4 5 bitri
 |-  ( A > B <-> B < A )