Find the sum of the first 15 terms of 2 + 6 + 18 + 54 + ...

Mathematics

1 answer:

dusya [7]3 years ago

4 0

S_n = n(first term + a_n)/2

n = 15

S_15 = 15(2 + a_n)/2

We need a_n.

a_n = first term + d(n - 1)

a_n = 2 + d(15 - 1)

1. Find d.

2. Plug d into expression to find a_n.

3. After finding a_n, plug back into

S_15 = 15(2 + a_n)/2 to find the sum of the first 15 terms.

Take it from here.

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According to this diagram what is tan 62

kicyunya [14]

The figure is not attached. So, I have attached it from the link- brainly.com/question/4198293

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Step-by-step explanation:

Label the triangle ABC as shown below.

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AB = 8, BC = 15, AC = 17, m∠ABC = 90°, m∠ACB = 28°, m∠BAC = 62°

The tangent of a given angle is given as the ratio of the opposite side and the adjacent side. The opposite side is the side opposite to the angle. The adjacent side is the other leg of the right angled triangle.

Here, the opposite side to angle A is BC and adjacent side is AB.

Therefore, the tan ratio of angle A is given as:

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