Power series

juztbenja

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Nov 25, 2021
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A function f take value -9 from x = 0. The n'th derivative is given by

Skjermbilde 2021-11-25 kl. 17.01.35.png

f is analytical. on the interval (-3,3). What is f(5/2)

So I've tried to use the formula for Maclaurin series so that I get: (4/3^n) * x^n. And then get the sum = 12/(3-x) and try to put in 5/2 for x, then get 24. But I don't get the answer I'm looking for. I also tried to do this f(5/2) = -9 + 24 = 15 which is also the wrong answer... What am I doing wrong? Feel kinda stupid right now XD
 
To get 123x\frac{12}{3-x} you need to start your series from n=0n=0, but you are starting from n=1n=1.
 
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