1. The problem statement, all variables and given/known data Find the length of r = theta^(2) for 0<=theta<=pi 2. Relevant equations Arc length s = antiderivative of sq rt (f (theta)^(2) + f (derivative theta)^(2)) 3. The attempt at a solution I have worked my way to the antiderivative of sq rt (theta^(4) + 4(theta)^(2)) but I'm not sure where to go from here. I've been looking for a trig identity that will help me thru the antiderivative and get rid of the sq. rt but haven't had any luck. Is there something I'm overlooking? Thanks in advance!