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2 years ago

A geometric sequence has a first term of 3 and a fourth term of 81÷8. Find the eighth term

Mathematics

1 answer:

tatuchka [14]2 years ago

5 0

Answer:

6561 / 128

Step-by-step explanation:

The nth term of a geometric sequence is:

a = a₁ (r)ⁿ⁻¹

The first term is 3, and the fourth term is 81/8.

81/8 = 3 (r)⁴⁻¹

27/8 = r³

r = 3/2

The eighth term is therefore:

a = 3 (3/2)⁸⁻¹

a = 6561 / 128

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2 years ago

An object is dropped from a small plane. As the object falls, its distance, d, above the ground after t seconds, is given by the

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The inequality can be used to find the interval of time taken by the object to reach the height greater than 300 feet above the ground is:

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Solution:

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Step-by-step explanation:

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Answer:

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Step-by-step explanation:

$\cos(\frac{\pi}{2})=0$ while $\sin(\frac{\pi}{2})=1$

So the equation becomes:

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2 years ago