General summations:
A shorthand notation is supplied to stand for sums with more than a few terms. This shorthand notation offers the Greek letter sigma (which denotes sum). If we have actually a dominion such as f (n) i beg your pardon assigns the worth f (n) to each integer n in the set of integers j, j+1, j+2, ... K, we can represent the sum as:
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=
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On the graphing calculator:

We will be using the sum feature and the seq attribute to job-related with a general summation.

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top top the calculator, we will translate a summation as follows:

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2nd STAT (LIST) → math #5 sum The style for sum is sum( list )where list will certainly be the terms of the rule
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second STAT (LIST) → OPS select #5 seq( The format for seq: expression, variable,starting value, ending value, increment.
While sequences have actually a domain of natural numbers, 1, 2, 3, 4, ..., in Func mode, the sequence command will accept essence domain values less than one. (In Seq mode, however, the sequence command will certainly accept just integer domain worths of 1 or greater.)

Example 1:Evaluate:
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notice that this sum starts v k = 2

Example 2: Evaluate:
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(For lull of entry, X
was offered as the variable in both instances above.If you great to use the designated variable, kind it into the calculator using the alpha key.)


If you think you are going to forget these commands:

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Another approach to instance 1:Type the number of terms needed right into L1.Type the ascendancy into L2.Add the answer manually on the HOME screen.
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Or, have the calculator execute the adding. If you carry out not want to add manually on the homescreen, you deserve to use the cumulative summation feature (cumSum) to add L2.Remember that example 1 starts v k = 2.

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To find cumSum( , walk to LIST(2nd STAT), arrowhead to OPSheading, and also choose #6 cumSum(.
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Enter cumSum(L2) together the pattern to recognize L3.
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The entry in tower L3corresponding to the worth 7in L1 will certainly be the sum.

Summations and also Sequences:
Sums, such together
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, whereby j = 1, may represent the summation the a sequence, referred to as a series.
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Remember, sequences have actually a domain of herbal numbers, 1, 2, 3, 4, .... In the sequence related troubles below, the beginning value in the summation will be greater than or same to 1.

Again, we will certainly be making use of the sum and also seq attributes of the calculator to find the summations. The summation is taken as:
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2nd STAT (LIST) → math #5 amount 2nd STAT (LIST) → OPS choose #5 seq(

Example 3: Evaluate:
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This example uses x together the variable,instead of making use of j. The x is simply much easier to get in into the calculator.

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Example 4: Evaluate:
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This example uses n together the variable -- obtained by engaging the alpha key.