How do you convert -3y= 7x^2-2xy 3y=7x22xy into a polar equation?

1 Answer
Oct 19, 2016

r=(3sintheta)/(sin2theta-7cos^2thetar=3sinθsin2θ7cos2θ

Explanation:

Use the substitution x=rcosthetax=rcosθ and y=rsinthetay=rsinθ
then we have
-3rsintheta=7r^2cos^2theta-2r^2sinthetacostheta3rsinθ=7r2cos2θ2r2sinθcosθ
divding by r and sin2theta=2sinthetacosthetasin2θ=2sinθcosθ
-3sintheta=r(7cos^2theta-sin2theta)3sinθ=r(7cos2θsin2θ)
r=-(3sintheta)/(7cos^2theta-sin2theta)=(3sintheta)/(sin2theta-7cos^2theta)r=3sinθ7cos2θsin2θ=3sinθsin2θ7cos2θ