Check series for uniform convergence on real numbers

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$$ \sum_{n=1}^{\infty} \frac{n^2}{1 + n} \frac{x^2 \sin x}{1 + n^5x^4}, E = \mathbb{R} $$ I tried to determine convergent subseries and something limited to use Abel - Dirichlet test, I can't find series that fit here.

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Hint: If $\sum f_n$ converges uniformly on a set $E,$ then we must have $\sup_E|f_n| \to 0.$ Is that true here?