Description: Move a conditional outside of an operation. (Contributed by Thierry Arnoux, 1-Oct-2018)
Ref | Expression | ||
---|---|---|---|
Assertion | ovif2 | |- ( A F if ( ph , B , C ) ) = if ( ph , ( A F B ) , ( A F C ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | oveq2 | |- ( if ( ph , B , C ) = B -> ( A F if ( ph , B , C ) ) = ( A F B ) ) |
|
2 | oveq2 | |- ( if ( ph , B , C ) = C -> ( A F if ( ph , B , C ) ) = ( A F C ) ) |
|
3 | 1 2 | ifsb | |- ( A F if ( ph , B , C ) ) = if ( ph , ( A F B ) , ( A F C ) ) |