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HOW TO USE EULER'S METHOD WITH TI89 CALCULATOR

 
Example: Find y(1) with stepsize, h = 0.5 for: y ′ = xy, y(0) = 1.
Steps Key Sequence Screens
1. Graph Slope Field  
2. Graph Solution Curve  
3. Change the Stepsize Press Diamond key, then F2 key (for WINDOW)
  Press down arrow (to tstep=)
  Press 0.5, then ENTER key
4. Graph Solution Curve Press DIAMOND key, then F3 key
5. Find y(1) Press F3 key (for Trace)
  Press 1, then ENTER (to input t = 1)
Note 1: The solution is at the bottom of the screen y(1) = 0.5.
Note 2: You can also scroll to right to find y(1.5), y(2), etc. and you can scroll to the left to find y(0.5), y(0), y(–0.5), etc.
Note 3: You can also use the TABLE to find y(1.5), y(2), y(0.5), y(0), y(–0.5), etc.