$\mathop {\lim }\limits_{x \to {2^ + }} {{2x + 1} \over {x - 2}}$

$\mathop {\lim }\limits_{x \to {2^ - }} {{2x + 1} \over {x - 2}}$

$\mathop {\lim }\limits_{x \to 0} \left( {{1 \over x} - {1 \over {{x^2}}}} \right)$

$\mathop {\lim }\limits_{x \to {2^ - }} \left( {{1 \over {x - 2}} - {1 \over {{x^2} - 4}}} \right)$