Expanding Cube Roots: Solving Limits with Maclaurin Series

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snoopies622
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A quiz at the end of Steven Krantz's Calculus Demystified includes the following problem:
Find
[tex] \lim_{x \to \infty} [ \sqrt[3]{x+1}<br /> -<br /> \sqrt[3]{x} ][/tex]
I see how one can use the Maclaurin series to get
[tex] \sqrt[3]{x+1} = 1 + \frac {x}{3} - \frac {x^2}{9} + \frac {5 x^3}{81} + . . .[/tex]
but trying it with the cube root of x gives me zero plus an endless series of undefined terms.
Is there a way to expand [itex]\sqrt[3]{x}[/itex] and solve this problem?
 
But why do you want expand that in series?
Isn't it by simple high school algebra :
Equation: (x+1)^(1/3) - x^(1/3) = 1 / (x^(2/3) + (x+1)^(2/3) + x^(1/3)(x+1)^(1/3)), a difference of cube roots written as a sum of cube-root products in the denominator.

for x>0?
 
Oh yeah, you're right zoki85 - thanks!

I also just realized that I could simply define y = x + 1, plug in y-1 for all the x's in the series above and there's the answer to my other question. :)