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HELP ASAP!!!!!!!!!!!!!

HELP ASAP!!!!!!!!!!!!!-example-1
User Merrydeath
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1 Answer

3 votes

Answer:

A.
\bold{a_n=-3\cdot\left(\frac18\right)^(n-1)}

Explanation:


\begin{cases}a_1=-3\\a_n=a_(n-1)\cdot\frac18\end{cases}\\\\\\a_2=a_(2-1)\cdot\frac18=a_1\cdot\frac18\\\\r=(a_2)/(a_1)=(a_1\cdot\frac18)/(a_1)=\frac18\\\\\\a_n=a_1\cdot r^(n-1)\\\\a_n=-3\cdot\left(\frac18\right)^(n-1)

User Chatar Singh
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