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O calculate the sum of the

First 10 term
nth term
in the series
(-1/6)+(1/-4)+(-3/8)+(-9/16)+…

1 Answer

2 votes

Answer:

Therefore, the tenth term in the series is (-1/6) * (-3)^(n-1).

Explanation:

AI-generated answer

Apologies for the confusion in the previous response. The series you provided is not a geometric series since the terms do not have a common ratio.

To find the sum of the first 10 terms in the series (-1/6) + (1/-4) + (-3/8) + (-9/16) + ..., we can calculate each term and then add them up.

The given series follows a specific pattern, where each term is obtained by multiplying the previous term by a negative power of 3.

Let's calculate the first 10 terms:

1st term = -1/6

2nd term = (1/-4) * (-1/3) = 1/12

3rd term = (-3/8) * (-1/3)^2 = -1/24

4th term = (-9/16) * (-1/3)^3 = 1/48

...

Continuing this pattern, we can calculate the remaining terms until the 10th term.

Now, let's add up the first 10 terms:

-1/6 + 1/12 + (-1/24) + 1/48 + ...

To simplify the calculations, we can find a common denominator for all the fractions. In this case, the common denominator is 48.

-1/6 can be written as -8/48, 1/12 as 4/48, -1/24 as -2/48, and so on.

-8/48 + 4/48 - 2/48 + ...

Now, we can simply add up the numerators:

(-8 + 4 - 2 + ...) / 48

The numerators form a pattern of -8, 4, -2, 1, -1, 1, -1, ...

The sum of this pattern is -5. Therefore, the numerator of the sum is -5, and the denominator remains 48.

So, the sum of the first 10 terms in the series is -5/48.

To find the nth term, we can observe that each term follows the pattern of multiplying the previous term by a negative power of 3. Therefore, the nth term can be calculated using the formula:

an = a * (-3)^(n-1),

where an represents the nth term, a is the first term, and n is the term number.

In this case, the first term a is -1/6.

Using the formula, we can find the nth term:

an = (-1/6) * (-3)^(n-1)

Therefore, the nth term in the series is (-1/6) * (-3)^(n-1).

User Oleg Dok
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