For Ellipse: The 2 circles made using the the ellipse center as their center, and major and minor axis of the ellipse as the dia. For Hyperbola: 2 Circles with centers at the center
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( ek¦sen·trik ′sərk·əlz ) (mathematics) For an ellipse, two circles whose centers are at the center of the ellipse and whose diameters are, respectively
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Eccentric circles are composed of two circles or spheres at least one of which contains
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