In this case, if we substitute $x = -1$ into the denominator, we get $(-1+4)(-1+2) = 3$, which is not zero. So we can apply the quotient law:
$$
\lim _{x \rightarrow-1} \frac{x-1}{(x+4)(x+2)} = \frac{\lim _{x \rightarrow-1} (x-1)}{\lim _{x \rightarrow-1}
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