How do you convert xy=x-2y+y^2 xy=x2y+y2 into a polar equation?

1 Answer

r=(cos theta-2*sin theta)/(sin theta* cos theta-sin^2 theta)r=cosθ2sinθsinθcosθsin2θ

Explanation:

just use the transformation equivalent

x=r cos thetax=rcosθ and y=r sin thetay=rsinθ in the equation

xy=x-2y+y^2xy=x2y+y2

so that xy=x-2y+y^2xy=x2y+y2 becomes

r cos theta* r sin theta=r cos theta-2* r sin theta+ (r sin theta)^2rcosθrsinθ=rcosθ2rsinθ+(rsinθ)2

canceling some of the r

r* cos theta* sin theta= cos theta-2* sin theta+ r sin^2 thetarcosθsinθ=cosθ2sinθ+rsin2θ

simplify to obtain

r* (cos theta* sin theta- sin^2 theta)= cos theta-2* sin thetar(cosθsinθsin2θ)=cosθ2sinθ

and

r=(cos theta-2* sin theta)/(cos theta* sin theta- sin^2 theta)r=cosθ2sinθcosθsinθsin2θ

have a nice day!