# How do you change (4, -1) from rectangular to cylindrical coordinates between [0, 2π)?

##### 1 Answer

Mar 4, 2015

I will assume you meant "polar coordinates" since cylindrical coordinates are 3-dimensional and you have only supplied 2-dimensional Cartesian coordinates.

From the graph:

and

Note that standard arctan functions will return a value which will need to be adjusted to compensate for the point being in the IV quadrant so

Depending upon the version used you will typically get

or

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