Illustration showing a circle formed by the intersection of a plane perpendicular to the axis of the…

Illustration of a plane parallel to the base passing through a cone (section made is a circle).

Illustration of a plane parallel to the base passing through a cone (section made is a circle).

Diagram of a cone with inscribed spheres and cut by various planes to depict the conic sections: circle,…

Diagram showing how to construct a conic when given the focus and the auxiliary circle. If the focus…

Diagram showing how to construct a conic when given the focus and the auxiliary circle. The focus is…

Diagram showing how to construct a conic when given the focus and the auxiliary circle. As the focus…

Illustration of an ellipse with major and minor axes, foci, and points on the ellipse. "An ellipse is…

Illustration showing an ellipse formed by the intersection of the surface of a cone with a plane neither…

An illustration showing how to construct an ellipse parallel to two parallel lines A and B. "Draw a…

Illustration of a cone cut by a plane that is not parallel to the base and does not intersect the base.

Illustration showing the definition of an ellipse as a conic section. The plane cuts the cone obliquely.

An illustration showing how to construct an ellipse. "With a as a center, draw two concentric circles…

An illustration showing how to construct an ellipse using a string. "Having given the two axes, set…

An illustration showing how to construct an ellipse using circle arcs. "Divide the long axis into three…

An illustration showing how to construct an ellipse using circle arcs. "Given the two axes, set off…

An illustration showing how to construct an ellipse. Given the two axes, set off half the long axis…

Diagram showing how to construct an ellipse when given the two foci and the length of the major axis…

Diagram of an ellipse that can used to illustrate the definition. "The constant ration between the distances…

Diagram that illustrates "The algebraic sum of the distances of any point from the foci of a conic is…

Diagram of an ellipse that can used to illustrate the different parts. Segment MN is the major axis,…

Diagram an ellipse with a tangent line that illustrates "A line through a point on the ellipse and bisecting…

Illustration showing a hyperbola as a curve formed by the intersection of the surface of a cone with…

Diagram depicting a cone with both nappes intersected by plane J to form a hyperbola.

Illustration of a cone cut by a plane parallel to the axis of the cone and perpendicular to the vertical…

Illustration showing the definition of a hyperbola as a conic section.

Diagram showing how to construct a hyperbola when given the two foci and the length of the major axis…

Diagram part of a hyperbola with a tangent line that illustrates "A line through a point on the hyperbola…

All triangles formed by a tangent and the asymptotes of an hyperbola are equal in area.

The lines joining any point on a conic to the two foci are equally inclined to the tangent and normal…

Illustration showing a parabola as a curve formed by the intersection of the surface of a cone with…

The segments between the point of intersection of two tangents to a conic and their points of contact…

Diagram of a cone intersected by plane J to form a parabola. Also pictured is a circle formed by the…

Illustration of a cone cut by a plane that is parallel to one of the elements of the cone. The curve…

Illustration showing the definition of a parabola as a conic section. The plane cuts the cone parallel…

Diagram showing how to construct a parabola when given the directrix (d), the focus (F) and the eccentricity…

Illustration showing intersecting straight lines meeting to form a triangle. It is formed by the intersection…