differentiate (xcos-1x)-sqrt(1-x^2) and use the result to evaluate the integration of cos-1dx between x=1 and x=0
similarily, prove that d/dx (xsin-1x)=sin-1x+x/(sqrt(1-x^2)). Hence find primitive of sin-1x and show that integration of sin-1x between x=1/2 and x=0 is pi/12+sqrt3/2-1
THankyou !

