Obtain Taylor Series at x0 = 0?

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Homework Statement


Is it possible obtain a Taylor serie at x0=0?

Homework Equations


f(x)= (\frac{x^4}{x^5+1})^{1/2}[/B]

The Attempt at a Solution


I think that it is not possible , since f' is not differenciable at x=0, since f' have the factor

(\frac{x^4}{x^5+1})^{-1/2}

but, for example wolfram yield a solution f approx x2

http://www.wolframalpha.com/widget/...0&podSelect=&showAssumptions=1&showWarnings=1
 
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Isn't it when ##x_0 = 1## that is the problem where it's not differentiable?
 
PeteSampras said:

Homework Statement


Is it possible obtain a Taylor serie at x0=0?

Homework Equations


f(x)= (\frac{x^4}{x^5+1})^{1/2}[/B]

The Attempt at a Solution


I think that it is not possible , since f' is not differenciable at x=0, since f' have the factor
f is continuous at 0, f' is continuous at 0, f'' is continuous at 0...
The function you're working with definitely has a Maclaurin series (i.e., a Taylor series in powers of x).
PeteSampras said:
 
I think that it is not possible , since f' is not differenciable at x=0, since f' have the factor

(x4/x5+1)−1/2

If you complete the calculation of f' by the chain rule, I think you'l find that factor isn't a problem.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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