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Does a plane curve with polar equation $$r=\lambda_1\cos^2\theta+\lambda_2\sin^2\theta$$ where both $\lambda_i>0$ have a name?

It's very similar to hippopede, also known as lemniscate of Booth, but not quite the same: hippopede equation can be written in the same way but with $r^2$ instead of $r$.

Here is how it looks like for $\lambda_2=1$ and $\lambda_1 \in \{\frac{1}{2}, 1, 2, 3, 4, 5\}$: enter image description here

Update: I realized that in my application it is more natural to put $r^2$ instead of $r$ in the equation above; hence what I appear to be dealing with is a hippopede after all. The family of curves displayed above is likely not to have any name (hard as I tried, I failed to find any).

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    $\begingroup$ I don't know but it is a nice family of curves ! $\endgroup$ – Claude Leibovici Nov 11 '15 at 10:50
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    $\begingroup$ I don't have a name either. What I can say is that it is a conchoid of a four-leaf rose. $\endgroup$ – J. M. is a poor mathematician Jul 23 '16 at 16:03
  • $\begingroup$ Out of curiosity, what was your application where this appeared? $\endgroup$ – gota Jun 6 at 14:19

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