Suppose we want to find the arc length of x(t)=cos(t), y(t)=sin(t) for t=0 to 2, using Wolfram | Alpha. Easy, the exact same thing that I wrote works. But now suppose we want to write a general formula* for the arc length of the curve, say from t=0 to a. Is there any way to do it by Wolfram | Alpha?
*Please notice that I know the general formula for this particular curve :) I used it as an example.