Rule for going from roots/asymptotes to intervals of a rational inequality

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Suppose I have a rational inequality, like

$$ \frac{(x-4)(x+4)}{(x-1)^2} < 0 $$

I can manually check between the roots (4,4) and asymptote (1) by plugging in value like 3 to see that:

$$ −4<x<1 \text{ and } 1<x<4 $$ Or in interval terms:

$$ (−4,1) \text{ and } (1,4) $$

Now, is there an algorithm to simply look at the roots/aymptotes, in this case (4,4,1), and know without plugging anything in what the interval or inequality of x is?

I know it's trivial in this case but imagine you had more massive polynomials causing lots of sign switching. Is there a technique for getting the inequalities/intervals from just looking at the roots/asymptotes of the rational function?

Note: I've been following along here https://tutorial.math.lamar.edu/Classes/Alg/SolveRationalInequalities.aspx Basically want to see if there's a way I can do these rational inequalities faster, and deal with bigger ones quickly.