A line through the focus and a line perpendicular to the directrix make the same angle with the tangent.
Any ray of light parallel to the axis of the parabola is reflected through the focus.
Expressions
| Name | Input | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Locus Eq |  |
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| Angle 1 Eq | |
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| Angle 2 Eq | |
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