Conic sections

• What Is the Eccentricity of an Ellipse?
  An ellipse’s eccentricity is e = c/a = √(1 − b²/a²), where a and b are its semiaxes and c is the center-to-focus distance.
• How to Change a Parabola to Canonical Form
  To put a rotated or translated parabola into canonical form, eliminate the cross term, complete the square, and shift to its vertex.
• How to Calculate an Ellipsoid’s Volume in Cylindrical Coordinates
  Set the ellipsoid's vertical bounds in cylindrical coordinates, include the Jacobian r, and integrate to obtain 4πabc/3 for semiaxes a, b, and c.