Hello from the book I am reading it defines the lemniscate as the locus for which the product of the distances r(adsbygoogle = window.adsbygoogle || []).push({}); _{1}and r_{2}with the coordinates x= a and x= -1 and y= 0 has the constant value of a^{2}.

I went about deriving the equation in polar coordinates from this locus, however I do not get the correct equation when the locus is defines as r_{1}x r_{2}= a^{2}but when r_{1}x r_{2}= a the correct equation is arrived at.

Is this simply a typo on behalf of the author?

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# Lemniscate locus

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