Page 98 - Calc for the Clueless
P. 98
As some of you know and the rest will find out soon, the exact answer is the In 4 = 1.386294361,
approximately.
Conic Sections
Most books call the circle, parabola, ellipse, and hyperbola conic sections without explaining why. These curves
are found by passing a plane through the truncated (cut-off) right circular cone pictured here. They are formed
as follows:
Circle—plane parallel to the top or bottom
Ellipse—plane on the top or bottom not parallel to the top or bottom but hitting all parts of the outside
Parabola—a plane parallel to an edge of the cone
Hyperbola—formed by a plane intersecting the top and bottom
Definition
Circle—The set of points equidistant from a point, the center (h,k). That distance is r, the radius.
