Lesson #161 Introduction to Polar coordinates

  
Quotes of the Day:
"A mathematician is a blind man in a dark room looking for
   a black cat which isn't there." -- Charles Darwin 
   (quoted by Jaime Escalante in the film, STAND and 
    DELIVER)

Objectives:
The student will plot points in the polar coordinate
  system.


1. Plotting Points
   Ask: How do you plot a point?
        In the Cartesian Coordinate System,
        you plot an x-coordinate, then a y-coordinate.
        Points are written as ordered pairs (x, y).   

        But there are other coordinate systems:
        In the Polar Coordinate System, you plot
        an angle and a radius.
        Points are written as (r, theta).

       

    In Polar Coordinates, r is a directed distance.
           theta is the angle from the positive x-axis and 
           measured in a counter-clockwise direction.

2. Examples of plotting points in the Polar Coordinate 
   System:

       
       

   Give some names for points B and D.  
   For each point, give 4 different names
     in the form:  (+, +), (+, -),
     (-, +), and (-, -).


3. Play Tic–Tac-Toe or "Connect Four" with Polar 
   Coordinates.

   Split the class into two teams.  

   The object of the game is to get four in a row –-
     along a radius, along a circle, or "diagonally."

   Take turns having students give coordinates. 

   Here is the Game Board:

       

Click here for a Game Board which can be printed

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