Description: Replacement of a subexpression by an equivalent one. (Contributed by Wolf Lammen, 27-Sep-2014)
Ref | Expression | ||
---|---|---|---|
Hypotheses | xchnxbi.1 | |
|
xchnxbi.2 | |
||
Assertion | xchnxbi | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | xchnxbi.1 | |
|
2 | xchnxbi.2 | |
|
3 | 2 | notbii | |
4 | 3 1 | bitr3i | |