How to estimate schwartz space functions?

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I'm currently learning about Schwartz spaces and I'm having difficulties when I'm trying to estimate the derivatives of the functions. For example when you have a function $e^{-ln(1+x^2)^N}$ and you want to verify whether it belongs to the Schwartz space or not. It's easy to compute 1st derivative(after that things go messy) and with that guess the general form which is a rational function $\frac{P(x)}{Q(x)}$ where $Q(x)$ doesn't have any singularities. Now we have that $(1+x^2)^N\frac{P(x)}{Q(x)}e^{-ln(1+x^2)^N}$. How to proceed here?