Calculus
posted by Katie .
Let F(x) be an antiderivative of sin^3(x). If F(1)=0 then F(8)=?
The answer: 0.632
How do I get to that answer? Do I find the antiderivatie and solve for F(x) when x=8?

Yes. Find the anti derivative and solve that answer for x = 8.

Alright, I found 1/4cos(x)^4 but I didn't get the right answer.
Did I dint the wrong antiderivative? Do I have to do reverse chain rule and get... (1/4cos(x))sin(x)^4? 
i am still lost can someone please explain

my anti deriv.. i got 1/4 Cosx^4 + C
what do i do next.. = [ 
Your antiderivative is not correct.
You need a u substitution. Or if you have not learned that try NINT in the calculator.
For the u substitution, let u = cos x and du=sinx . (this is after you changed the integral to sin^3x = sin^2x *sinx =(1cos^2x)(sinx). Don't forget the  sign in front of the integral too. Then do the u sub