## Calculus 8th Edition

$(-\infty,-\sqrt 5]$ U $[\sqrt 5, \infty)$
Simplify the expression on one side $x^2-5\geq0$ Identify the key numbers by equating to zero $(-\infty,-\sqrt 5]$ $(\infty,\sqrt 5]$ $[\sqrt 5,\sqrt 5]$ Assign a test value for each interval to determine the sign $(-\infty,-\sqrt 5]$ U $[\sqrt 5, \infty)$