HomeHome Metamath Proof Explorer < Previous   Next >
Related theorems
GIF version

Theorem pm5.32ri 490
Description: Distribution of implication over biconditional (inference rule).
Hypothesis
Ref Expression
pm5.32i.1 (φ → (ψχ))
Assertion
Ref Expression
pm5.32ri ((ψφ) ↔ (χφ))

Proof of Theorem pm5.32ri
StepHypRef Expression
1 pm5.32i.1 . . 3 (φ → (ψχ))
21pm5.32i 489 . 2 ((φψ) ↔ (φχ))
3 ancom 333 . 2 ((ψφ) ↔ (φψ))
4 ancom 333 . 2 ((χφ) ↔ (φχ))
52, 3, 43bitr4 158 1 ((ψφ) ↔ (χφ))
Colors of variables: wff set class
Syntax hints:   → wi 2   ↔ wb 127   ∧ wa 196
This theorem is referenced by:  2eu5 1071  dfoprab2 3021  th3qlem1 3250  xpsnen 3339  pw2en 3348
This theorem was proved from axioms:  ax-1 3  ax-2 4  ax-3 5  ax-mp 6
This theorem depends on definitions:  df-bi 128  df-an 198
metamath.org