it seems as though you're stuck with the quotient rule, how about you try one and I'll see where you're having problems and try to help you
1.differentiate the function using the quotient rule.
fx=cos(5x)/x^4
2.fx=(x+3)/(x-2). Derivitive?
3.
Derivitive?
4.
derivitive?
5.
derivitive
6.Find the second derivative of the function.
f(x) = 2x + 25x−2
7.Find f '''(x).