Metamath Proof Explorer


Theorem trpredeq1d

Description: Equality deduction for transitive predecessors. (Contributed by Scott Fenton, 2-Feb-2011)

Ref Expression
Hypothesis trpredeq1d.1 φ R = S
Assertion trpredeq1d φ TrPred R A X = TrPred S A X

Proof

Step Hyp Ref Expression
1 trpredeq1d.1 φ R = S
2 trpredeq1 R = S TrPred R A X = TrPred S A X
3 1 2 syl φ TrPred R A X = TrPred S A X