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Find a12 for the geometric sequence -4, -2, -1, -1/2, ...

User Fuk
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1 Answer

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9514 1404 393

Answer:

-1/512

Explanation:

The first term is -4, and the common ratio is -2/-4 = 1/2. Then the n-th term is ...

an = -4ยท(1/2)^(n-1)

and the 12th term is ...

a12 = -4(1/2)^(12 -1) = -4/2048

a12 = -1/512

User Getmemd
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