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HOW TO FIND THE SUM OF A SERIES WITH TI89 CALCULATOR

Example 1: Find .
Steps Key Sequence Screens
1. Select Sum Function Press F3 (for Calc menu)
  Press 4 (for 'sum(')
2. Input General Term for Sequence Use n for variable, then comma key
3. Input Variable of Expression Press ALPHA, then 6 (for n), then comma key
4. Input Lower Limit of Sum Press 1, then comma key
5. Input Upper Limit of Sum Press DIAMOND key, then CATALOG key (for infinity), then ')'
6. Evaluate Series Press ENTER