Absolutely lost on this:

r=8cotx (x should be in degrees).

I tried converting this (as well as others) but I seem to just get nowhere after I turned cot into cosx/sinx.

Thanks.

Edit: The equation above should be converted to rectangular form.

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- Mar 17th 2009, 09:49 PMCheaglesConverting polar coordinates.
Absolutely lost on this:

r=8cotx (x should be in degrees).

I tried converting this (as well as others) but I seem to just get nowhere after I turned cot into cosx/sinx.

Thanks.

Edit: The equation above should be converted to rectangular form. - Mar 18th 2009, 12:16 AMmr fantastic
- Mar 18th 2009, 04:57 AMHallsofIvy
I think I would have done this a slightly different way:

$\displaystyle r= 8 cot(\theta)= 8\frac{cos(\theta)}{sin(\theta)}$ so

$\displaystyle r sin(\theta)= 8 cos(\theta)$

Multiplying on both sides of the equation by r,

$\displaystyle r(r sin(\theta))= 8 r cos(\theta)$

and

$\displaystyle \sqrt{x^2+ y^2}y= 8x$

Now squaring both sides will give what Mr. fantastic got.