Theorem mp1i 10

Description: Drop and replace an antecedent. (Contributed by Stefan O'Rear, 29-Jan-2015.)

Hypotheses

Ref	Expression
mp1i.a	|- ph
mp1i.b	|- ( ph -> ps )

Assertion

Ref	Expression
mp1i	|- ( ch -> ps )

Proof of Theorem mp1i

Step	Hyp	Ref	Expression
1		mp1i.a	. . 3 |- ph
2		mp1i.b	. . 3 |- ( ph -> ps )
3	1, 2	ax-mp 7	. 2 |- ps
4	3	a1i 9	1 |- ( ch -> ps )

Syntax hints:   -> wi 4

This theorem was proved from axioms:  ax-1 5  ax-mp 7

This theorem is referenced by:  poirr2  4717  relcoi2  4848  tfrlemi14d  5947  findcard2d  6348  findcard2sd  6349  ac6sfi  6352  cauappcvgprlemladd  6756  caucvgprprlemmu  6793  caucvgsrlemfv  6875  recidpirqlemcalc  6933  recidpirq  6934