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Math Help - Can someone explain how I do this one?

  1. #1
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    Can someone explain how I do this one?

    Find a polar equation of the conic with focus at the pole and the given eccentricity and directrix.
    e=3/2,ysinΘ=1
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  2. #2
    MHF Contributor
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    There is a rule for eccentricity. e > 1 tells you it is what sort of conic? Hint: You're going to need another focus and directrix.

    Conics look like this in polar coordinates: r = \frac{ep}{1\pm e\sin(\theta)} parallel to the polar axis, or

    r = \frac{ep}{1\pm e\cos(\theta)} perpendicular to the polar axis.

    You have e = 3/2 -- Alarm goes off! This is a hyperbola.

    If you mean r\sin(\theta) = 1, then we have a horizontal line. (Pretty obvious that this tranlsates to y = 1?). Okay, what form is that?

    We are so close...

    Note: Is that enough information for uniqueness?
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