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Systems
The Logic Resource Center
Public Alpha
Systems
Open options
Systems
Biconditional Introduction
Constants
≡
Systems
LRC_F
OLI
The Logic Book
LRC
LRC_P
LRC_O
Start a Problem
→
Biconditional Introduction
i
i.
ϕ
A
ii.
ψ
iii
iii.
ψ
A
iv.
ϕ
⋮
v.
ϕ
≡
ψ
≡I: i, ii, iii, iv
Forward from Sub-Proofs
Enter a biconditional
Cite the lines you intend to use as premises and conclusions
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Preview shown for the
Typed Forward Strict
derivation type in the
LRC
system
