Theorem orcd

Description: Deduction introducing a disjunct. A translation of natural deduction rule \/ IR ( \/ insertion right), see natded . (Contributed by NM, 20-Sep-2007)

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

Proof

Step	Hyp	Ref	Expression
1		orcd.1	⊢ ( 𝜑 → 𝜓 )
2		orc	⊢ ( 𝜓 → ( 𝜓 ∨ 𝜒 ) )
3	1 2	syl	⊢ ( 𝜑 → ( 𝜓 ∨ 𝜒 ) )