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by **ppat** on Wed Mar 04, 2009 5:50 am

(5/2)^-2 + (2/1)^-3

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by **wibblyangelica** on Wed Mar 04, 2009 2:33 pm

ppat wrote:(5/2)^-2 + (2/1)^-3

Remember that when a fraction (a/b)^-n is considered you can do a couple of things:
1. You can distribute the exponents to both the numerators and the denominators.
2. Flip the fraction in the parantheses and then do #1.

When you do either step 1 or 2, you will have to find the LCD (Lowest common denominator) to combine the fractions.

:thumb:

by **stapel_eliz** on Wed Mar 04, 2009 6:41 pm

ppat wrote:(5/2)^-2 + (2/1)^-3

To review the rules for working with negative exponents, try here. Then follow the steps provided earlier:

. . . . . $\left(\frac{5}{2}\right)^{-2}\, +\, \left(\frac{2}{1}\right)^{-3}$

. . . . . $\left(\frac{2}{5}\right)^2\, +\, \left(\frac{1}{2}\right)^3$

. . . . . $\frac{4}{25}\, +\, \frac{1}{8}$

...and so forth.

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need help simplifying (5/2)^-2 + (2/1)^-3

need help simplifying (5/2)^-2 + (2/1)^-3

Re: need help simplifying (5/2)^-2 + (2/1)^-3