# How do you find the domain and range of y= -1/2 x ^2?

Oct 9, 2015

Domain: $\mathbb{R}$
Range: $\mathbb{R} \le 0$
$\left(- \frac{1}{2} {x}^{2}\right)$ is defined for all Real values of $x$
$\Rightarrow$ the Domain is $\mathbb{R}$
$y$ is $\le 0$ for all values of $x$
$\Rightarrow$ the Range is $\mathbb{R} \le 0$