i cant seem to get this right Any help is greatly appreciate

i cant seem to get this right. Any help is greatly appreciated ! Thanks!

Evaluate the indefinite integral by using the given substitution to reduce the integral to standard form. 20s3 ds/ , u = 5 - s4

Solution

u = 5-s^4

du = -4s^3 ds

s^3 ds = -du/4

Thus:

int 20s^3/(5-s^4) ds =

int -20/4 * 1/u du =

int -5/u du =

-10u + C =

-10(5 - s^4) + C