Description: The set of N-times differentiable points is a subset of the domain of the function. (Contributed by Stefan O'Rear, 16-Nov-2014) (Revised by Mario Carneiro, 11-Feb-2015)
Ref | Expression | ||
---|---|---|---|
Assertion | dvnbss | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | dvnff | |
|
2 | 1 | ffvelcdmda | |
3 | 2 | 3impa | |
4 | cnex | |
|
5 | simp2 | |
|
6 | 5 | dmexd | |
7 | elpm2g | |
|
8 | 4 6 7 | sylancr | |
9 | 3 8 | mpbid | |
10 | 9 | simprd | |