Simple polar to cartesian conversion

Thread starter Trousers
Start date Mar 4, 2008
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Cartesian Polar

Mar 4, 2008

Trousers

Find a Cartesian equation for the curve.
18=rcos \theta

\frac{\ 18}{cos \theta}= \sqrt{x^2+y^2}

how do I get rid of the cosine?

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Mar 4, 2008

HallsofIvy

Science Advisor

Homework Helper

Don't divide by it! What is r cos(\theta) in terms of x and y coordinates? In other words, x= ? , y= ? in polar coordinates.

Mar 4, 2008

Trousers

x=18 is the solution. I can't believe it.

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