Uniform convergence, indicator functions and Schwartz functions

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I'd like to know if following sequence converges uniformly: $$f_n (x)=f(x)\chi_{[-n,n]}(x)$$ Where $f\in\mathcal S(\mathbb R)$ and $\chi_{[-n,n]}$ is indicator function of interval [-n,n].

Now we know that $f_n=f$ on interval [-n,n] and outside that interval $f(x)<C/x^2$ where C is specific for a given schwartz function. We can now put: $$\epsilon=C/n^2$$ and therefore for every $\epsilon>0$ there exists $n$ so that $|f_n(x)-f(x)|<\epsilon$ for every $x\in \mathbb R$. We have proven uniform convergence on $\mathbb R$.

In the book that I am reading they are using it in a proof but the indicator function is first convoluted with mollifier. They use the properties of the mollified function in other parts of the proof. I want to know if my proof is correct even though the sequence does not consist of continuous functions.

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According to the comments the proof is correct so indeed the product of Schwartz function and indicator function can converge uniformly to the Schwartz function.