Conversion of polar equations

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How would you say have some equation in the polar coordinate system as: $$r=3\sin3\theta $$

I know how to find the are of one petal of this shape using polar coordinate integration, but say if I convert this to its Cartesian form this exact polar equation using $ x = r \cos \theta$ , $y= r \sin\theta$, then how would I find the area in when it is in the Cartesian form?

Could anyone give me some clear steps, this will really help me understand better. Thanks in advance.

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As you know we have $$ \sin 3\theta = 3 \sin \theta -4 \sin ^3 \theta $$

Thus your equation in Cartesian coordinates gets a little bit complicated. $$ r = 3 \sin (3\theta ) \implies r^2=3r (3\sin \theta -4\sin ^3 \theta )$$ $$ x^2+y^2=9y -12y \frac {y^2}{x^2+y^2}$$

It is not any easier than polar form.