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Find the 8th Term for the Geometric Sequence for which a1 - 3 and r = -2

User Melvin
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1 Answer

4 votes

Answer:

-384

Explanation:

geometric sequence : every new element is generated by multiplying the previous element always with the same number r.

a(n) = a(n-1) * r

a(n) = a(1) * r^(n-1)

so, a(1) = 3, r = -2

a(8) = ?

a(8) = a(1) * r^7 = 3 * (-2)^7

a negative number to an uneven power is again a negative number.

so, (-2)^7 = -128

3 * -128 = -384 = a(8)

User Walino
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