The parametric equations of a curve are: x = cos2θ y = sinθcosθ. Find the cartesian form of the equation.

x = cos2θ  y = sinθcosθcos2θ = cos2 θ  - sin2θ cos2 θ  + sin2θ  = 12cos2 θ  = 1 + cos2θ cos2 θ  = 1/2(1 + x)2sin2θ  = 1 - cos2θ sin2θ  = 1/2 (1 - x)y2= sin2θcos2 θy2=  ( 1/2(1 + x)) . (1/2 (1 - x))4y2 = 1 - x2 x2 + 4y2 = 1

AN

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