# How do you evaluate the function p(x)=x^2-2 for p(-2)?

May 14, 2018

$p \left(- 2\right) = 2$

#### Explanation:

$p \left(x\right) = {x}^{2} - 2$

When $x = - 2$, $p \left(x\right) = p \left(- 2\right)$

$p \left(- 2\right) = {\left(- 2\right)}^{2} - 2$
$\textcolor{w h i t e}{p \left(- 2\right)} = 2$

May 14, 2018

I tried this:

#### Explanation:

When you write:

$p \left(- 2\right)$

it means that you want to evaluate your function for $x = - 2$, so you need to subtitute $x$ for $- 2$ in $p$:

$p \left(- 2\right) = {\left(- 2\right)}^{2} - 2$

as you can see $x$ became $- 2$. Let us evaluate the value of our function at this value of $x$:

$p \left(- 2\right) = \textcolor{red}{4} - 2 = 2$

because: ${\left(- 2\right)}^{2} = 4$