Metamath Proof Explorer


Theorem tpeq123d

Description: Equality theorem for unordered triples. (Contributed by NM, 22-Jun-2014)

Ref Expression
Hypotheses tpeq1d.1 φA=B
tpeq123d.2 φC=D
tpeq123d.3 φE=F
Assertion tpeq123d φACE=BDF

Proof

Step Hyp Ref Expression
1 tpeq1d.1 φA=B
2 tpeq123d.2 φC=D
3 tpeq123d.3 φE=F
4 1 tpeq1d φACE=BCE
5 2 tpeq2d φBCE=BDE
6 3 tpeq3d φBDE=BDF
7 4 5 6 3eqtrd φACE=BDF