How to Rationalize the Denominator of a Radical Expression?

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Homework Statement


Rationalize the denominator..
[tex] \frac{1}{\sqrt[3]{a}+\sqrt[3]{b}+\sqrt[3]{c}}[/tex]


Homework Equations



Algebraic equations.

The Attempt at a Solution


So using the form
a3 + b3 + c3 - 3abc= (a + b + c)(a2 + b2 + c2 - ab - bc - ca)

So it becomes


[tex] \frac{\sqrt[3]{a^2}+\sqrt[3]{b^2}+\sqrt[3]{c^2} -\sqrt[3]{ab}-\sqrt[3]{bc}-\sqrt[3]{ca} }{a + b + c - 3 \sqrt[3]{abc}}[/tex]


Actually I don't know what to do next
If i try (a+b)(a-b) then it doesn't work out ...
 
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Use

[tex]x^3-y^3=(x-y)(x^2+xy+y^2)[/tex]

ehild
 


ehild said:
Use

[tex]x^3-y^3=(x-y)(x^2+xy+y^2)[/tex]

ehild

Mark44 said:
I don't see how this applies to the OP's problem.

[tex]x-y=\frac{x^3-y^3}{x^2+xy+y^2}[/tex]

:wink:
 


Of course! An emoticon is worth a thousands words.

If there were a more suitable emoticon for "I'm sure you get it now" I would use that one instead.

:smile: << (don't kill me for this :-p)
 


Yup got it!
Thanks!

(Checked it out with my teacher ... its right!)