1. Definition of an Ellipse:
An ellipse is the set of points in a plane whose distances from two fixed points have a constant sum.
2. Distribute a copy of the Ellipse paper to each student. Have each student trace out an ellipse while I do one at the overhead. The purpose of this is to have students understand the definition of the ellipse by locating points which satisfy the definition.
Ellipse Paper
3. Develop the equation for an ellipse with center at the origin and major axis on the x-axis.
Let the foci be (-c, 0) and (c, 0)
Let the constant sum = 2a (the major axis)
Click here for the full proof of the formula for the ellipse
4. The general forms for an ellipse are:
5. Examples:
6. Area of an Ellipse