Metamath Proof Explorer


Theorem ifpororb

Description: Factor conditional logic operator over disjunction in terms 2 and 3. (Contributed by RP, 21-Apr-2020)

Ref Expression
Assertion ifpororb if- φ ψ χ θ τ if- φ ψ θ if- φ χ τ

Proof

Step Hyp Ref Expression
1 dfifp2 if- φ ψ χ θ τ φ ψ χ ¬ φ θ τ
2 df-or ψ χ ¬ ψ χ
3 2 imbi2i φ ψ χ φ ¬ ψ χ
4 df-or θ τ ¬ θ τ
5 4 imbi2i ¬ φ θ τ ¬ φ ¬ θ τ
6 3 5 anbi12i φ ψ χ ¬ φ θ τ φ ¬ ψ χ ¬ φ ¬ θ τ
7 ifpimimb if- φ ¬ ψ χ ¬ θ τ if- φ ¬ ψ ¬ θ if- φ χ τ
8 dfifp2 if- φ ¬ ψ χ ¬ θ τ φ ¬ ψ χ ¬ φ ¬ θ τ
9 imor if- φ ¬ ψ ¬ θ if- φ χ τ ¬ if- φ ¬ ψ ¬ θ if- φ χ τ
10 ifpnot23d ¬ if- φ ¬ ψ ¬ θ if- φ ψ θ
11 10 orbi1i ¬ if- φ ¬ ψ ¬ θ if- φ χ τ if- φ ψ θ if- φ χ τ
12 9 11 bitri if- φ ¬ ψ ¬ θ if- φ χ τ if- φ ψ θ if- φ χ τ
13 7 8 12 3bitr3i φ ¬ ψ χ ¬ φ ¬ θ τ if- φ ψ θ if- φ χ τ
14 1 6 13 3bitri if- φ ψ χ θ τ if- φ ψ θ if- φ χ τ