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What is the 8th for the geometric sequence 6,561;−2,187;729;−243;…

User Neocotic
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1 Answer

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1st let's calculate r the common ratio:
r = (-2187)/(6561) = (729)/(-2187) = -1/3

Value of nth term = a₁.rⁿ⁻¹, where a₁= 1st term and n, the rank

Value of nth term = 6561r⁸⁽⁻¹⁾ = 6561.(-1/3)7

Value of nth term = -3
User Mdubez
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