(adsbygoogle = window.adsbygoogle || []).push({}); 1. Sum the Geometric Series 1-x+x^{2}-x^{3}+x^{4}

and hence simplify the function

[f(x)]^{4}= 1 - x^{5}

1-x+x^{2}-x^{3}+x^{4}

2. Relevant equations

3. Not sure I quite get understand this properly, as my attempt doesnt seem quite right.

Basically Ive gotten

S=1-x+x^{2}-x^{3}+x^{4}

S=1-1+x-x^{2}+x^{3}

x x

which then subtracted becomes

s(1 - 1) = (1-1)+2x+x+x

x x

= 1 +4x

x

Then, putting that into the simplifying function part gives me

f(x) =

1 -x5

-1 +4x

x

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# Homework Help: Sum of Geometric Series

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