Calculus 2 Series Question: Prove the inequality

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jrcalcuphysic
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This was already posted by someone else but an answer wasn't received so I thought I'd repost. Any help is appreciated.

Homework Statement



Use the Maclaurin series for cosx and the Alternating Series Estimation Theorem to show that

[tex]\frac{1}{2} - \frac{x^2}{24} < \frac{1-cosx}{x^2} < \frac{1}{2}[/tex]


Homework Equations



[tex] <br /> cosx = 1 - \frac{x^2}{2} + \frac{x^4}{4} - \cdot \cdot \cdot = \sum_{n=0}^\infty \frac{x^{2n}(-1)^{n}}{(2n)!} <br /> [/tex]


The Attempt at a Solution



Using the Alternating Series Estimation Theorem I know the error is less than the next term:

[tex] |error| < \frac{x^{2n+2}}{(2n + 2)!}[/tex]

I have no idea how to answer this.
 
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