Integral of a quadratic function
http://integralcalc.com/ Learn how to calculate the integral of a quadratic function by completing the square. To complete this problem, you'll need to complete the square of the quadratic, then use trigonometric substitution to calculate the integral. Once you've used trigonometric substitution to simplify the integral, you'll use integration by parts to simplify further. Finally, you'll back substitute to get the answer in terms of x instead of theta. In order to do this, you'll need to use the values from the right triangle you drew when you set up your trigonometric substitution problem.