<s>[INST] What is that function? Polynomial? Is it a polynomial or rational polynomial or else?
$y = \dfrac{a}{x^4} + \dfrac {b}{x^2} + c$
I need to fit a curve to a discrete data of that form, so I need to know what fitting to use.
 [/INST] We have $$\frac{a}{x^4}+\frac{b}{x^2}+c=\frac{a}{x^4}+\frac{bx^2}{x^4}+\frac{cx^4}{x^4}=\frac{a+bx^2+cx^4}{x^4}$$
This is a rational function.
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