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I know that: the first term of the sequence is -2, and the fifth term is -1/8

.
What do you know?

1 Answer

7 votes

Solution

Here the first term = -2

5th term = -1/8

Now we have to find the common ratio (r)

Fifth term A5 = -1/8

-1/8 =
a_(1) r^(4)

Here
a_(1) = -2

Plug in
a_(1) = -2 in the fifth term and find the value of r.

-1/8 = -2
r^(4)

r^4 = 1/16

Taking 4th root, we get

r = 1/2

Now let's find the second term.

first term *r = -2 *1/2 = -1

2nd term = first term * 1/2 = -1

3rd term = second term * 1/2 = -1 * 1/2 = -1/2

4th term = 3rd term *r = -1/2 *1/2 = -1/4

Thank you :)


User Shyam Achuthan
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