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HOW TO GRAPH A POLAR EQUATION WITH TI89 CALCULATOR

Steps Key Sequence Screens
1. Change MODE Press MODE key
  Press right arrow key
  Press 3 (for 3:POLAR)
  Press ENTER (to Save)
2. Input Equation into r1 Press DIAMOND key, then F1 (for Y=)
  Type equation*, then ENTER
*Use theta for the independent variable by pressing the 'diamond' key, then the caret (i.e., ^) key.
3. Graph Equation Press DIAMOND key, then F3 (for GRAPH)
NOTE 1: You can ZOOM, TRACE and evaluate the same as with cartesian functions.
NOTE 2: ZoomSqr is probably best for polar equations.