http://img529.imageshack.us/img529/3044/bin2od4.th.jpg [Broken](adsbygoogle = window.adsbygoogle || []).push({});

http://img529.imageshack.us/img529/9734/bin1ml5.th.jpg [Broken]

The problem and solution are attached above. Firstly, why is the expansion valid for (mod x/(1+x)) < 1, and not just for mod(x)<1?

Also, I do not understand how from (mod x/(1+x)) < 1 , the value of x>-0.5 comes about. Why greater than 0.5, and not less than 0.5?

Thanks

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# Homework Help: Binomial expansion

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