y=a(sin2θ-2θcos2θ)

0:09:44

If x=a(cos2θ+2θsin2θ) , y=a(sin2θ-2θcos2θ), find d2y/dx2 at θ= pi/8

0:08:38

The parametric equations of a curve are x =a(2θ − sin2θ), y = a(1− cos2θ). Show that dy/dx =cotθ