What is the antiderivative of sinx^3?

1 Answer
Jun 13, 2017

If you mean (sinx)^3, please see below. If you mean sin(x^3), I can't help.

Explanation:

Here is one possibility

int (sinx)^3 dx = int sin^2x sinx dx

= int ((1-cos^2 x) sinx dx

= int sinx dx + int underbrace(cos^2x)_u underbrace((-sinx) dx)_(du)

= -cosx + cos^3x/3 +C

As is typical of expressions involving trigonometric functions, there are other ways to express this family of functions.

(WolframAlpha gives 1/12(cos(3x)-9cosx)+C and simplifies the difference between our basic answers to 0.)