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What is the sum of the first six terms of the geometric series 4 − 12 36 − . . . ?

User Damd
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1 Answer

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The formula to use for the sum of n terms is as follows:

S_(n)=(a(1-r^(n)))/(1-r)
r = -3, n = 6.

S_(6)=(4(1-(-3)^(6)))/(1-(-3))=-728
User Sharee
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