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what is the name of a shape made from two circles with different radii that intersect each other?

Sort of like a snowman shape, made of a big and a small ball of snow, melted together a bit! :-) Thanks

Arturo Magidin
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lucy
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1 Answers1

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I do know that a "figure 8" shape is known as a lemniscate: you can read more here: http://en.wikipedia.org/wiki/Lemniscate. But I'm not sure if that's what you're looking for. What you seem to describe is the union of two circles (of different size) which intersect at two points.

Wikipedia has an interesting "taxonomy" of various shapes and variations of familiar shapes, etc.: http://en.wikipedia.org/wiki/List_of_geometric_shapes

amWhy
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  • FWIW: the (usual) lemniscate (Bernoulli, Gerono) is not a union of two circles. One can however specialize the hippopede $r^2=4b(a-b\sin^2\theta)$ to the case $a=b$... – J. M. ain't a mathematician Apr 30 '11 at 00:16
  • @J.M. No, no. Of course the usual lemniscate is not a union of two circles. I was simply giving the closest approximation I could think of ("figure 8"). But good to make explicit. Thanks. – amWhy Apr 30 '11 at 00:36
  • Thank you Amy for your help, that wasn't quite what I was after, but it was nice to get a friendly reply :-) – lucy May 01 '11 at 10:00