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Metamath Proof Explorer


Theorem pm4.71rd

Description: Deduction converting an implication to a biconditional with conjunction. Deduction from Theorem *4.71 of WhiteheadRussell p. 120. (Contributed by NM, 10-Feb-2005)

Ref Expression
Hypothesis pm4.71rd.1
|- ( ph -> ( ps -> ch ) )
Assertion pm4.71rd
|- ( ph -> ( ps <-> ( ch /\ ps ) ) )

Proof

Step Hyp Ref Expression
1 pm4.71rd.1
 |-  ( ph -> ( ps -> ch ) )
2 1 pm4.71d
 |-  ( ph -> ( ps <-> ( ps /\ ch ) ) )
3 2 biancomd
 |-  ( ph -> ( ps <-> ( ch /\ ps ) ) )