Reflection Property of an Ellipse

Reflection Property of an Ellipse

At any point $$p$$ on an ellipse, the tangent at $$p$$ makes equal angles with the lines joining $$p$$ to the two foci.

$$\angle(\text{tangent},PS_1)=\angle(\text{tangent},PS_2)$$

Usage

- Used in reflection and optical-property problems involving the ellipse.