Theorem 3mix2i 1128

Description: Introduction in triple disjunction. (Contributed by Mario Carneiro, 6-Oct-2014.)

Hypothesis

Ref	Expression
3mixi.1	⊢ φ

Assertion

Ref	Expression
3mix2i	⊢ (ψ ∨ φ ∨ χ)

Proof of Theorem 3mix2i

Step	Hyp	Ref	Expression
1		3mixi.1	. 2 ⊢ φ
2		3mix2 1125	. 2 ⊢ (φ → (ψ ∨ φ ∨ χ))
3	1, 2	ax-mp 5	1 ⊢ (ψ ∨ φ ∨ χ)

This proof depends on syntax axioms:   ∨ w3o 933

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8

This proof depends on definitions:  df-bi 177  df-or 359  df-3or 935

This theorem is used by:  tpid2  3831