Question 453961
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*[tex \LARGE \ \ \ \ \ \ \ \ \ \ A_n\ =\ 972\,\cdot\,\left(\frac{1}{3}\right)^{n\,-\,1}]


So for the 9th term, replace *[tex \Large n] with 9:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ A_9\ =\ 972\,\cdot\,\left(\frac{1}{3}\right)^{8}]


The rest is just calculator arithmetic.  Hint:  Your calculator is going to give you a repeating decimal for an answer.  Multiply the calculator result by 3, then do it again, and continue until the calculator gives you a whole number.  That is the numerator of your fractional answer.  3 raised to the power of the number of times you multiplied by 3 is the denominator.


John
*[tex \LARGE e^{i\pi} + 1 = 0]
My calculator said it, I believe it, that settles it
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