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HOW TO FIND DERIVATIVES WITH TI89 CALCULATOR

Steps Key Sequence Screens
1. Set Up Differentiator Press F3, then 1 (for d( differentiate)
2. Type the Function  
3. Input Variable Press comma, then the variable
4. Execute Derivative Press ')', then ENTER
NOTE: If you typed the function into y1(x), then use d(y1(x),x).
To evaluate the derivative at a point:
  Follow Steps 1 – 3 above
5. Evaluate Press ')', then | key
  Type x, then =
  Type value for x, then ENTER