Theorem orim2i

Description: Introduce disjunct to both sides of an implication. (Contributed by NM, 6-Jun-1994)

	Ref	Expression
Hypothesis	orim1i.1	⊢ ( 𝜑 → 𝜓 )
Assertion	orim2i	⊢ ( ( 𝜒 ∨ 𝜑 ) → ( 𝜒 ∨ 𝜓 ) )

Proof

Step	Hyp	Ref	Expression
1		orim1i.1	⊢ ( 𝜑 → 𝜓 )
2		id	⊢ ( 𝜒 → 𝜒 )
3	2 1	orim12i	⊢ ( ( 𝜒 ∨ 𝜑 ) → ( 𝜒 ∨ 𝜓 ) )