ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  impbid21d Structured version   Unicode version

Theorem impbid21d 119
Description: Deduce an equivalence from two implications. (Contributed by Wolf Lammen, 12-May-2013.)
Hypotheses
Ref Expression
impbid21d.1
impbid21d.2
Assertion
Ref Expression
impbid21d

Proof of Theorem impbid21d
StepHypRef Expression
1 impbid21d.1 . . 3
21a1i 9 . 2
3 impbid21d.2 . . 3
43a1d 22 . 2
52, 4impbidd 118 1
Colors of variables: wff set class
Syntax hints:   wi 4   wb 98
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia2 100  ax-ia3 101
This theorem depends on definitions:  df-bi 110
This theorem is referenced by:  impbid  120  pm5.1im  162
  Copyright terms: Public domain W3C validator