Hey mathematicians, please help me solve this calculus problem!

im really stuck on this one. i had to skip the class friday and i have a test tomorrow :(

it's (2/3)(9-(x^2))^(2/3)  
in english: nine minus x squared, to the power of 2/3, multiplied by 2/3
 
 you do a u-substitution. U = 9-x^2 
this makes dU = -2x dx 
 
the substituted equation becomes: integral of u^(1/2) 
which is: 2/3*u^(3/2)

unsubstituting gives you: (2/3)(9-(x^2))^(2/3)      

Hey dudes. www.wolframalpha.com Best site ever. (excluding Giant Bomb, ofc.)

This is why I am a journalism major

Also, I just remembered. There's a fancy website out there that only us sexy math people know about. But I'm willing to disclose it to you because I am so sexy and awesome. 
It is called: http://www.wolframalpha.com     
The problem you asked to be answered is something that wolframalpha can do easily. Just type in integrate(squareroot(9-x^2)(-2x)) 
It's like typing into a calculator, except it is even better. Just make sure you get the parentheses right.

"

Also, I just remembered. There's a fancy website out there that only us sexy math people know about. But I'm willing to disclose it to you because I am so sexy and awesome. 
It is called: http://www.wolframalpha.com     
The problem you asked to be answered is something that wolframalpha can do easily. Just type in integrate(squareroot(9-x^2)(-2x)) 
It's like typing into a calculator, except it is even better. Just make sure you get the parentheses right.

"

thanks guys 

also  http://www.cramster.com/

"

Also, I just remembered. There's a fancy website out there that only us sexy math people know about. But I'm willing to disclose it to you because I am so sexy and awesome. 
It is called: http://www.wolframalpha.com     
The problem you asked to be answered is something that wolframalpha can do easily. Just type in integrate(squareroot(9-x^2)(-2x)) 
It's like typing into a calculator, except it is even better. Just make sure you get the parentheses right.

"