Theorem orim1i 503

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

Hypothesis

Ref	Expression
orim1i.1	|- (ph -> ps)

Assertion

Ref	Expression
orim1i	|- ((ph \/ ch) -> (ps \/ ch))

Proof of Theorem orim1i

Step	Hyp	Ref	Expression
1		orim1i.1	. 2 |- (ph -> ps)
2		id 19	. 2 |- (ch -> ch)
3	1, 2	orim12i 502	1 |- ((ph \/ ch) -> (ps \/ ch))

Syntax hints:   -> wi 4   \/ wo 357

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8

This theorem depends on definitions:  df-bi 177  df-or 359

This theorem is referenced by:  19.34  1663  r19.45av  2769  leconnnc  6219