The Logic Resource Center
Public Alpha
Systems
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Systems
The Logic Resource Center
Public Alpha
Systems
Open options
Systems
Disjunction Introduction Right
Constants
∨
Systems
OLI
Start a Problem
→
Disjunction Introduction Right
i.
ϕ
⋮
ii.
(
ϕ
∨
ψ
)
∨IR: i
Forward
Select an available formula
Specify the aditional disjunct
Click "Apply"
Backward
Select a goal disjunction
Click "Apply"
Preview shown for the
Point And Click
derivation type in the
OLI
system