so there is a power series(adsbygoogle = window.adsbygoogle || []).push({});

S4^n z^(3n)

and upper limit being infinity and lower limit being 0. (S means sigma)

then my book says, ak = 4^ (k/3) if k = 0, 3, 6...

and ak equals 0 otherwise.

i dont get how they came up for the value of ak

i might be missing something silly ...

any clues?

thanks!

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# Limit of a series

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