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Find the sum of the geometric series given a₁ = 2, r = -3, and n = 8.A. 1/2B.-3107OC.-3280D. -3780Reset Selection

Find the sum of the geometric series given a₁ = 2, r = -3, and n = 8.A. 1/2B.-3107OC-example-1
User Katoch
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1 Answer

3 votes

The formula to calculate the sum of a geometric sequence is given to be:


S_n=(a_1(1-r^n))/(1-r)

The question has the following parameters:


\begin{gathered} a_1=2 \\ r=-3 \\ n=8 \end{gathered}

Therefore, the sum will be:


\begin{gathered} S_8=(2(1-(-3)^8))/(1-(-3)) \\ S_8=-3280 \end{gathered}

The correct option is OPTION C.

User Eritrean
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