Write a polar equation of a conic that has its focus at the origin and satisfies the given conditions.Parabola, directrix $y = - 3$
A) $r = \frac { 3 } { 1 - \sin \theta }$
B) $r= \frac { 3 } { 1 + \sin \theta }$
C) $r= \frac { 1 } { 1 - 3 \cos \theta }$
D) $r = \frac { 3 } { 1 + 3 \cos \theta }$
E) none of these

Question

Quizplus · Accepted Answer

A parabola with a directrix $y = -3$ and focus at the origin has the polar equation $r = \frac{ed}{1 - e\sin\theta}$ where $e = 1$ for a parabola and $d = 3$.

Write a Polar Equation of a Conic That Has Its y=−3y = - 3y=−3

Write a Polar Equation of a Conic That Has Its $y = - 3$