Here's the question you clicked on:
SUROJ
how to integrate sqrt(a^2(sinx)^2+b^2(cosx)^2) from 0<=x<=pi
Are you sure you typed it correctly? See the attached image for mathematica calculations, it's taking a good while for it to calculate the indefinite integral
what is that elliptice in the answer?
It's an elliptic integral, something that I have never studied. http://en.wikipedia.org/wiki/Elliptic_integral