(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Find the term in the expansion of (x-(2/x^2))^14 which is of the form constant/x.

3. The attempt at a solution

I have worked out the general expression. (14|r) x^14-r * (-2/x^2)^r

However I can only work out this problem by trial and error. I know that in this case r=5, however I didn't solve it by equation. What equation would I need to construct to get this answer r=5? I know that for the answer to be constant/x the power of x on the denominator can only be 1 greater than the power of x on the numerator.

How do I construct an equation with r to solve this?

Thanks

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# Homework Help: Finding a term in a binomial expnasion

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