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Math Help - Graph of the polar equation at the pole

  1. #1
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    Graph of the polar equation at the pole

    Find the tangents at the pole for r=2(1-sin theta)

    I've been having alot of trouble with this concept. So far Ive tried setting r= to 0 and solving for theta but i dont know if thats right...
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  2. #2
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    There's a little more to it than that.

    \frac{dy}{dx}=\frac{rcos(t)+sin(t)\cdot\frac{dr}{d  t}}{-rsin(t)+cos(t)\cdot\frac{dr}{dt}}

    Find the derivative of r=2(1-sin(t)) and plug it all in.

    Then, set to 0 and solve for theta.

    I just used t for less typing.

    Upon doing all that, you should get \frac{sin(2t)-cos(t)}{cos(2t)+sin(t)}

    Just set sin(2t)-cos(t)=0 and solve for t.

    Spoiler:
    cos(t)(2sin(t)-1)=0

    cos(t)=0 \;\ or \;\ 2sin(t)-1=0
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  3. #3
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    thanks. so for my next problem its r=3sin2t
    so i would solve for dy/dx, set the numerator equal to zero, and solve for t?
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