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simple binomial query, please help... watch

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    how do you apply binomial expansion to a fraction for example: {(2+x)/(1-x)}^1/2

    thanks if you can help me out guys, im stumped!
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    Generally:

     (1+x)^n = 1 + nx + \frac{(n)(n-1)}{2!}x^2 + \frac{(n)(n-1)(n-2)}{3!}x^3 ...

    Where n is a fraction and the absolute value of x is <1.

    This is applicable to the example you posted.

    Notice  ((2+x)(1-x))^{\frac{1}{2}} = (2+x)^{\frac{1}{2}} \cdot (1-x)^{-\frac{1}{2}}
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    sorry i meant, i can handle when n is a fraction, but when the actual expression is a fraction, in my example (2+x)/(1-x), thanks again
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    I'd personally make it, the top multiplied by the bottom ^-1/2, or whatever it was. Then i'd do two binomial expansions for each, and then multiply at the end. Wouldn't take that long given that those are relatively simple, but i'm sure there's a quicker way our teacher neglected to tell us.
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    See my edit.
 
 
 
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Updated: June 14, 2006

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