Description: Prove if ( A e. CH , A , ~H ) e. CH . (Contributed by David A. Wheeler, 8-Dec-2018) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Assertion | ifchhv | |- if ( A e. CH , A , ~H ) e. CH |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | helch | |- ~H e. CH |
|
2 | 1 | elimel | |- if ( A e. CH , A , ~H ) e. CH |