Description: Swap the second and third terms in a double subtraction. (Contributed by NM, 19-Aug-2005)
Ref | Expression | ||
---|---|---|---|
Assertion | sub32 | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | addcom | |
|
2 | 1 | 3adant1 | |
3 | 2 | oveq2d | |
4 | subsub4 | |
|
5 | subsub4 | |
|
6 | 5 | 3com23 | |
7 | 3 4 6 | 3eqtr4d | |