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CLASSICAL FIRST-ORDER LOGIC WITH EQUALITY
Propositional calculus
Mixed connectives
orim1d
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orim2d
Metamath Proof Explorer
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Theorem
orim1d
Description:
Disjoin antecedents and consequents in a deduction.
(Contributed by
NM
, 23-Apr-1995)
Ref
Expression
Hypothesis
orim1d.1
⊢
φ
→
ψ
→
χ
Assertion
orim1d
⊢
φ
→
ψ
∨
θ
→
χ
∨
θ
Proof
Step
Hyp
Ref
Expression
1
orim1d.1
⊢
φ
→
ψ
→
χ
2
idd
⊢
φ
→
θ
→
θ
3
1
2
orim12d
⊢
φ
→
ψ
∨
θ
→
χ
∨
θ