6.4 Polar Coordinates

What you’ll learn about Polar Coordinate System Coordinate Conversion Equation Conversion Finding Distance Using Polar Coordinates … and why Use of polar coordinates sometimes simplifies complicated rectangular equations and they are useful in calculus.

The Polar Coordinate System A polar coordinate system is a plane with a point O, the pole, and a ray from O, the polar axis, as shown. Each point P in the plane is assigned polar coordinates as follows: r is the directed distance from O to P, and  is the directed angle whose initial side is on the polar axis and whose terminal side is on the line OP.

Example Plotting Points in the Polar Coordinate System

Example Plotting Points in the Polar Coordinate System

Finding all Polar Coordinates of a Point

Coordinate Conversion Equations

Example Converting from Polar to Rectangular Coordinates

Example Converting from Polar to Rectangular Coordinates

Example Converting from Rectangular to Polar Coordinates

Example Converting from Rectangular to Polar Coordinates

Example Converting from Polar Form to Rectangular Form

Example Converting from Polar Form to Rectangular Form

Example Converting from Polar Form to Rectangular Form

Example Converting from Polar Form to Rectangular Form

Example Converting from Polar Form to Rectangular Form

Quick Review

Quick Review Use the Law of Cosines to find the measure of the third side of the given triangle. 4. 40º 8 10 5. 35º 6 11

Quick Review Solutions

Quick Review Solutions Use the Law of Cosines to find the measure of the third side of the given triangle. 4. 40º 8 10 5. 35º 6 11 6.4 7