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Calculate the ag term of the geometric sequence with a2 = 16 and r=-1/4?

User Raj Advani
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1 Answer

6 votes

a_2=16

Common ratio r = - 1/4


\begin{gathered} a_n=a_1\cdot(r^(n-1)) \\ r=(a_2)/(a_1) \\ a_1=(a_2)/(r)=(16)/(-(1)/(4)) \\ a_1=-64 \end{gathered}
\begin{gathered} a_9=-64_{}\cdot(-(1)/(4))^(9-1)=-64\cdot(-(1)/(4))^8 \\ a_9=-64\cdot(1)/(65536) \\ a_9=-(1)/(1024) \end{gathered}

User ITWorker
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