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Imparcticle
Mar13-05, 02:01 PM
I'm not sure how to do this:

[3x-1/3 + x5/3y] / x2/3

this is what i did:

[3 + x5/3y ]/ x1/3x2/3

[3+ x5/3y]/x

the answer to the problem is the same as what I have except instead of x^5/3, its x^2.

help.

dextercioby
Mar13-05, 02:05 PM
Of course it is.Put it like that:

\frac{\frac{3}{x^{\frac{1}{3}}}+x^{\frac{5}{3}}y}{ x^{\frac{2}{3}}}

Do you see where that x^{2} is coming from...?

Daniel.

arildno
Mar13-05, 02:05 PM
Your 1.step, that is, extracting x^{-\frac{1}{3}} from the parenthesis has been done incorrectly.
Try to figure out why.

A_I_
Mar13-05, 04:34 PM
u can take x^2/3 in factor for the numerator, u will have:

[x^2/3(3x^-1 +xy)]/x^2/3

then u simplify and obtain

3/x + xy

which leads to (3 + yx^2)/x

Imparcticle
Mar13-05, 11:16 PM
Of course it is.Put it like that:



Do you see where that x^{2} is coming from...?


no.

Your 1.step, that is, extracting from the parenthesis has been done incorrectly.
Try to figure out why.


I don't see it.


u can take x^2/3 in factor for the numerator, u will have:

[x^2/3(3x^-1 +xy)]/x^2/3


how are you factoring a x^2/3 when the smallest power is -1/3 ? if you factor that out, x^5/3 should be x^1/3.


help.

Data
Mar13-05, 11:28 PM
\frac{\frac{3}{x^{\frac{1}{3}}} + x^{\frac{5}{3}}y}{x^{\frac{2}{3}}} = { \left( \frac{3}{x^{\frac{1}{3}}} + x^{\frac{5}{3}}y \right) \over x^{\frac{2}{3}}}\cdot \frac{x^{\frac{1}{3}}}{x^{\frac{1}{3}}} = \frac{3 + x^2y}{x}

I only posted this because I think you're getting more confused by the replies so far. Try to take a lesson from the method I used to simplify (that is, multiplying by 1 is a good idea sometimes!).