Partial Fractions: Reducing x^5, Example Help Needed

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To simplify the expression x^5/(x^3 - x), start by factoring out common terms. Dividing both the numerator and denominator by x gives x^4/(x^2 - 1). Polynomial long division can further reduce the numerator's degree, leading to x^2 + (x^2/(x^2 - 1)). This method allows for a clearer understanding of how to handle the expression without directly providing the final answer. Understanding these steps is crucial for mastering partial fractions.
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I`ve been asked to complete the following expresion
\frac{x^5}{x^3 - x}

I know i`m supossed to reduce the numerator, but i`m a little stuck getting started.

The problem i have is how do you reduce x^5?

is it simply x^3(x^2)? but then how do you get rid of the x^3

AAHH i`m lost.

I obviously don`t want you to give me the answer so an example of your choice would be greatly appreciated.

Cheers
 
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You can first divide both denominator and numerator by 'x'. They have 'x' in common. So:
\frac{x ^ 5}{x ^ 3 - x} = \frac{x ^ 4}{x ^ 2 - 1}
You can use 'polynomial long division' to reduce the degree of the numerator. You can click here for more information.
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Or you can also do it a little bit differently:
You notice that x4 = (x2)(x2). But the denominator is x2 - 1, so:
x4 = x2(x2 - 1) + x2.
Now:
\frac{x ^ 4}{x ^ 2 - 1} = \frac{x ^ 2(x ^ 2 - 1) + x ^ 2}{x ^ 2 - 1} = x ^ 2 + \frac{x ^ 2}{x ^ 2 - 1}
Now just do the same for \frac{x ^ 2}{x ^ 2 - 1}:
\frac{x ^ 2}{x ^ 2 - 1} = \frac{x ^ 2 + ... - ...}{x ^ 2 - 1} = ...
Viet Dao,
 

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