Question

lim r² - r / r² + r - 2 r-> 1

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Answer 1

Olá!

$\\ \mathsf{\lim_{r \to 1} \frac{r^2 - r}{r^2 + r - 2} =} \\\\\\ \mathsf{\lim_{r \to 1} \frac{r(r - 1)}{(r + 2)(r - 1)} =} \\\\\\ \mathsf{\lim_{r \to 1} \frac{r}{(r + 2)} =} \\\\\\ \mathsf{\frac{1}{1 + 2}} = \\\\\\ \boxed{\mathsf{\frac{1}{3}}}$