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HOW TO GRAPH THE DIRECTION FIELD WITH TI89 CALCULATOR

Steps Key Sequence Screens
1. Change Graphing Mode Press MODE key
  Press right arrow key
  Press 6 (for DIFF EQUATIONS)
  Press ENTER (to save)
2. Input Equation Press DIAMOND key, then F1 (for Y=)
  Type in equation
Note: Use t as independent variable AND use explicit multiplication.
3. Change Graph Formats Press DIAMOND key, then | key
Set the following: Axes = ON, Labels = ON, Solution Method = RK, Fields = SLPFLD. To change use arrow keys.
  Press ENTER (to SAVE)
4. Graph Press DIAMOND key, then F3 (for Graph)
5. Change Window Settings, if Necessary Press DIAMOND key, then F2 (for Window)
  Press DIAMOND key, then F3
NOTE: If you have an initial condition, then complete the following steps.
Steps Key Sequence Screens
6. Input Condition Press DIAMOND key, then F1 (for Y=)
  Type in x-value of condition into t0= and y-value into Yi1=
7. Graph Press DIAMOND key, then F3 (for Graph)