Theorem iftrued 3338

Description: Value of the conditional operator when its first argument is true. (Contributed by Glauco Siliprandi, 11-Dec-2019.)

Hypothesis

Ref	Expression
iftrued.1	|- ( ph -> ch )

Assertion

Ref	Expression
iftrued	|- ( ph -> if ( ch , A , B ) = A )

Proof of Theorem iftrued

Step	Hyp	Ref	Expression
1		iftrued.1	. 2 |- ( ph -> ch )
2		iftrue 3336	. 2 |- ( ch -> if ( ch , A , B ) = A )
3	1, 2	syl 14	1 |- ( ph -> if ( ch , A , B ) = A )

Syntax hints:   -> wi 4   = wceq 1243   ifcif 3331

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-in2 545  ax-io 630  ax-5 1336  ax-7 1337  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-11 1397  ax-4 1400  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-i5r 1428  ax-ext 2022

This theorem depends on definitions:  df-bi 110  df-nf 1350  df-sb 1646  df-clab 2027  df-cleq 2033  df-clel 2036  df-if 3332

This theorem is referenced by:  expinnval  9258