how to solve this derivative?

diff((x(t)^-8+y(t)^-8-1)^-(1/8),x(t))

Answer 1

[thanos zisopoulos]

 i want to derivative  with regard to f(x)  this x(t)^-8+y(t)^-8-1)^-(1/8)

[Torsten]

What is f(x) ?

[thanos zisopoulos]

sorry i mean x(t)