Metamath Proof Explorer


Theorem ensymd

Description: Symmetry of equinumerosity. Deduction form of ensym . (Contributed by David Moews, 1-May-2017)

Ref Expression
Hypothesis ensymd.1
|- ( ph -> A ~~ B )
Assertion ensymd
|- ( ph -> B ~~ A )

Proof

Step Hyp Ref Expression
1 ensymd.1
 |-  ( ph -> A ~~ B )
2 ensym
 |-  ( A ~~ B -> B ~~ A )
3 1 2 syl
 |-  ( ph -> B ~~ A )