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Propositional calculus
Propositional calculus: miscellaneous
bj-imbi12
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bj-biorfi
Metamath Proof Explorer
Ascii
Unicode
Theorem
bj-imbi12
Description:
Uncurried (imported) form of
imbi12
.
(Contributed by
BJ
, 6-May-2019)
Ref
Expression
Assertion
bj-imbi12
⊢
φ
↔
ψ
∧
χ
↔
θ
→
φ
→
χ
↔
ψ
→
θ
Proof
Step
Hyp
Ref
Expression
1
imbi12
⊢
φ
↔
ψ
→
χ
↔
θ
→
φ
→
χ
↔
ψ
→
θ
2
1
imp
⊢
φ
↔
ψ
∧
χ
↔
θ
→
φ
→
χ
↔
ψ
→
θ