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Calculate the sum of the first 8 terms of the arithmetic sequence where

A8=−1 and the common difference
d=−8.

A. 15
B. 17
C. 19
D. 21

User Terrific
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1 Answer

3 votes

Final answer:

The sum of the first 8 terms of the arithmetic sequence is -232

Step-by-step explanation:

To calculate the sum of the first 8 terms of an arithmetic sequence, we can use the formula: Sn = (n/2)(2a + (n-1)d), where Sn is the sum of the first n terms, a is the first term of the sequence, and d is the common difference between the terms.

In this case, we are given that A8 = -1 and d = -8. Plugging these values into the formula, we get: S8 = (8/2)(2*(-1) + (8-1)*(-8)) = 4*(-2 + 7*(-8)) = 4*(-2 - 56) = 4*(-58) = -232.

Therefore, the sum of the first 8 terms of the arithmetic sequence is -232.

User Liah
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