The Logic Resource Center

The Logic Resource Center

Public Alpha

The Logic Resource Center

Public Alpha

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Equivalence

Constants: &∨~≡⊃
Systems: The Logic Book

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Equivalence

i.

ϕ≡ψ

ii.

(ϕ⊃ψ)&(ψ⊃ϕ)

Equiv: i

i.

(ϕ⊃ψ)&(ψ⊃ϕ)

ii.

ϕ≡ψ

Equiv: i

i.

ϕ≡ψ

ii.

(ϕ&ψ)∨(~ϕ&~ψ)

Equiv: i

i.

(ϕ&ψ)∨(~ϕ&~ψ)

ii.

ϕ≡ψ

Equiv: i

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Backward

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Click "Apply"

Preview shown for the Point And Click derivation type in the The Logic Book system