Optical Property of Foci

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The foci have the property that the lines from the foci to a point on the curve make equal angles to the tangent. Hence, light shone from one focus reflects off the curve and passes through the other focus.

Expressions

Name Input
Angle 2 Eq Derive Input Maple Input MathML Input Mathematica Input Maxima Input Mupad Input TI-Nspire Input text Input Image
Angle 1 Eq Derive Input Maple Input MathML Input Mathematica Input Maxima Input Mupad Input TI-Nspire Input text Input Image