# A-level Mathematics/OCR/FP2/Polar Coordinates

< A-level Mathematics | OCR | FP2

We have usually used cartesian co-ordinates(x,y).Polar coordinates are an alternative system which can describe position of a point.In polar co-ordinates any point can be described in terms of its distance and direction from a fixed point O.

Each point *P* in the plane is assigned polar coordinationates according to the following rules:

**r** is the directed distance from *O* to *P*.

**θ** is the directed angle between the polar axis (usually a ray from point *O* to the east) to the line *OP*.