Greetings! Lets solve this shall we ?
We notice the requirement to find the most general anti-derivative of the function f(x) = 5/x4 .
So, we integrate it as
5 ∫ (1/x4) dx = 5 ∫ x-4 dx = 5(x-3/ (-3)) + C = (-5/3)x-3 + C or (-5 / 3x3) + C
I hope this helped!