differentiability at x=0

[man111]

A value of k such that [tex]f(x)= x^k[/tex] is (n-1) times differentiable at 0 but not (n) times differentiable at 0 is .

[ptj]

Ако това е цялото условие, то [tex]k=n-1[/tex]. Следва от определението за производна.

[drago]

For example k=n-1/2 satisfies the condition.
May be there is some fun in this problem, but certainly the right place for it is not in this section!

[man111]

so What should be the final answer of that question..

[mkmarinov]

Any [tex]k \in (n-1; n)[/tex].