**Cartesian equation: **

*x*^{4} = *a*^{2}(*x*^{2}-*y*^{2})

**Polar equation: **

*r*^{2} = *a*^{2}cos(2*θ*)sec^{4}(*θ*)

**Click below to see one of the Associated curves.**

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This curve is also known as the

**Other Web site:**

JOC/EFR/BS January 1997

The URL of this page is:

http://www-history.mcs.st-andrews.ac.uk/Curves/Eight.html