Metamath Proof Explorer


Theorem ifov

Description: Move a conditional outside of an operation. (Contributed by AV, 11-Nov-2019)

Ref Expression
Assertion ifov
|- ( A if ( ph , F , G ) B ) = if ( ph , ( A F B ) , ( A G B ) )

Proof

Step Hyp Ref Expression
1 oveq
 |-  ( if ( ph , F , G ) = F -> ( A if ( ph , F , G ) B ) = ( A F B ) )
2 oveq
 |-  ( if ( ph , F , G ) = G -> ( A if ( ph , F , G ) B ) = ( A G B ) )
3 1 2 ifsb
 |-  ( A if ( ph , F , G ) B ) = if ( ph , ( A F B ) , ( A G B ) )