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3 years ago

what is the sum of an 8th term geometric series if the first term is -11, the last term is 180,224, and the common ratio is -4

Mathematics

1 answer:

Mumz [18]3 years ago

4 0

The sum of n terms is given from the first term and the common ratio by

$S_{n}=a_{1}\dfrac{r^{n}-1}{r-1}$

For your given values of a1=-11, r=-4, n=8, the sum of 8 terms is

$S_{8}=(-11)\dfrac{(-4)^{8}-1}{-4-1}=(-11)\dfrac{65535}{-5}\\\\=144177$

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Help pls what's the common difference

horsena [70]

Answer:

#9: 5

#10: -2

#11: -1.5

Step-by-step explanation:

#9: 3,8,13,18,23,(28),(33),(38),.. Go up by 5 each time, so the common difference is 5.

#10: 11,9,7,5,3,(1),(-1),(-3),... Go down (-) by 2 each time, so the common difference is -2.

#11: 3, 1.5, 0, -1.5, -3, (-4.5), (-6), (-7.5),... Go down (-) by 1.5 each time, so the common difference is -1.5.

7 0

2 years ago

Zero pairs are two numbers that multiply to get 0. True False

Neko [114]

That is actually true. Everything thats multiplied by 0 eaquals 0.

4 0

2 years ago

Read 2 more answers

The human eye contains approximately 9.1 x 10^7 rod cells and 4.5 x 10^6 cone cells . Samuel subtracts 9.1-4.5 and says there ar

Paul [167]

Samuel is incorrect because he didn't subtract the power of the numbers.

<h3>How many more rod cells are there?</h3>

The number of rod and cone cells in the human eye is written in scientific notation. Scientific notation is used in expressing large numbers in smaller numbers. To write a number in scientific notation, the number is written as a decimal number, between 1 and 10 and multiplied by a power of 10. For example, 1 x 10² is equivalent to 100

(9.1 x 10^7) - (4.5 x 10^6)

= (9.1 - 4.5) x 10^(7 - 6)

4.6 x 10 = 46

To learn more about scientific notation, please check: brainly.com/question/25334755

#SPJ1

6 0

1 year ago

Help please!!! I need it!

Grace [21]

Answer:

1300.62

Step-by-step explanation:

thank me later lolol.

8 0

2 years ago

An observer standing on a cliff 320 feet above the ocean measured angles of depression of the near and far sides of an island to

Gnesinka [82]

Answer:

154.10 Feets

Step-by-step explanation:

Given the following :

Height (h) of cliff = 320 feet

Angle of depression of near side = 16.5°

Angle of depression of far side = 10.5°

Using trigonometry :

We can obtain x and y as shown in the attached picture :

Tanθ = opposite / Adjacent

Adjacent = height of cliff = 320 Feets

For the near side :

Tanθ = opposite / Adjacent

Tan (16.5°) = x / 320

0.2962134 = x / 320

x = 0.2962134 * 320

x = 94.788318 Feets

For the far side :

Tanθ = opposite / Adjacent

Tan (10.5°) = x / 320

0.1853390 = x / 320

x = 0.1853390 * 320

x = 59.308494 Feets

Length of island = (59.308494 + 94.788318) feet

= 154.10 Feets

5 0

3 years ago