Are fractional polynomials linearly independent?

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dipole
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i.e., does the set of functions of the form,

[itex]\{ x^{\frac{n}{m}}\}_{n=0}^{\infty}[/itex] for some fixed [itex]m[/itex] produce a linearly independent set? Either way, can you give a brief argument why or why not?

Just curious :)
 
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If you have any linear combination between a finite number of these elements, this relation can be written as

[tex]a_ny^n+a_{n-1}y^{n-1}+...+a_1y = 0[/tex]

where [itex]y = x^{\frac{1}{m}}[/itex] and a_n is non-zero. However, a polynomial of degree n has exactly n zeroes, which means that this is impossible.
 
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