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The following equation is a conic section written in polar coordinates.=51 + 5sin(0)Step 2 of 2: Find the equation for the directrix of the conic section.

The following equation is a conic section written in polar coordinates.=51 + 5sin-example-1
User Ankush Soni
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1 Answer

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For a conic with a focus at the origin, if the directrix is


y=\pm p

where p is a positive real number, and the eccentricity is a positive real number e, the conic has a polar equation


r=(ep)/(1\pm e\sin\theta)

if 0 ≤ e < 1 , the conic is an ellipse.

if e = 1 , the conic is a parabola.

if e > 1 , the conic is an hyperbola.

In our problem, our equation is


r=(5)/(1+5\sin\theta)

If we compare our equation with the form presented, we have


\begin{cases}e={5} \\ p={1}\end{cases}

Therefore, the directrix is


y=1

User John Fish
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