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Find the sum of the first n terms of the following arithmetic sequence; a1=-5 d=-6 ; n=10

User Fsarter
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Final answer:

The sum of the first 10 terms of an arithmetic sequence with a first term of -5, a common difference of -6, and n=10 is -320.

Step-by-step explanation:

The student is asking to find the sum of the first n terms of an arithmetic sequence with the first term a1 = -5, the common difference d = -6, and n = 10. The formula to find the sum of the first n terms (Sn) of an arithmetic sequence is:

Sn = n/2 * (2a1 + (n - 1)d)

Substituting the given values into this formula, we get:

S10 = 10/2 * (2(-5) + (10 - 1)(-6))

S10 = 5 * (-10 - 54)

S10 = 5 * (-64)

S10 = -320

Therefore, the sum of the first 10 terms of the given arithmetic sequence is -320.

User Henfs
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