What the is the polar form of y^2 = (x-3y)^2-x^2 ?

1 Answer
Oct 27, 2016

We know the relations

x=rcostheta and y =rsintheta

Again x^2+y^2=r^2

where (r,theta) are the polar coordinates of a point corresponding to the rectangular coordinates (x,y)

The given equation in rectanglar form is

y^2=(x-3y)^2-x^2

=>y^2=x^2-6xy+9y^2-x^2

=>8y^2=6xy

=>8y^2=6xy

=>8r^2sin^2theta=6xxrcosthetaxxrsintheta

=>8sin^2theta=6costhetasintheta

=>4(1-cos2theta)=3sin2theta

=>3sin2theta+4cos2theta=4

This is the polar form of the given equation.