Calculus
# Limits of Functions

Find the value of

$\lim_{x \to -2} \frac{x^2+ 5x+6}{x+2}.$

Evaluate

$\lim_{x \to 1} \frac{x-1}{\sqrt{x+3} -2}.$

If $a$ and $b$ satisfy

$\lim_{x \to 0} \frac{x}{\sqrt{x+a} - b} = 6,$

what is $a+b$?

Evaluate

$\lim_{x \to \infty} \left( \sqrt{x^2 + 4x - 1} - x \right).$