Ok I know you have to do trig substitution but its been awhile since I've done so : /
The problem is : The integral of 2Sqrt(1-x^2)
The original posted question was wrong. See here: http://www.mathhelpforum.com/math-he...tml#post413788
This thread is being kept open in case other members want to follow up on the posted question.
You might find this website useful: - Wolfram|Alpha
Be sure to click on Show steps.