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Re: Please help me simplify this expression.
Posted:
Jan 24, 2005 2:20 AM


aaronhunter@gmail.com wrote: : : Problem: [x(x+2)^(1/2) + (x+2)^(1/2) ] / (x+2)^(3/2) : : I first separate out the problem and combine the lower exponents to get : [x((2/(x+2)) + 1/(x+2)] / (x+2)
I'm not sure what you mean by that, but the result is clearly incorrect. Put x=2 (so that the square roots are easy) into the original expression and get 3/8. In your expression, x=2 gives 5/16.
You want to change the denominator from (x+2)^(3/2) to just (x+2). A standard trick for simplifing fractions is to multiply or divide the numerator and denominator by the same amount. Try (x+2)^(1/2). That will give you the denominator you desire, but a simplier numerator than you have above.
Perhaps a better approach would be to multiply the numerator and denominator by (x+2)^(1/2). That still eliminates the fractional exponents AND also eliminates the negative exponents at the same time.
Robert )\/  Burnaby South Secondary School \ orewood@olc.ubc.ca  Beautiful British Columbia Mathematics & Computer Science  (Canada)
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