# How do you evaluate f(x)=12x^2-19 for f(1/2)?

Nov 9, 2016

$f \left(\frac{1}{2}\right) = - 16$

#### Explanation:

Substitute $\frac{1}{2}$ for $x$ in $f \left(x\right)$ giving:

$f \left(\frac{1}{2}\right) = 12 {\left(\frac{1}{2}\right)}^{2} - 19 \implies$

$f \left(\frac{1}{2}\right) = 12 \left(\frac{1}{2}\right) \left(\frac{1}{2}\right) - 19 \implies$

$f \left(\frac{1}{2}\right) = 12 \left(\frac{1}{4}\right) - 19 \implies$

$f \left(\frac{1}{2}\right) = 3 - 19 \implies$

$f \left(\frac{1}{2}\right) = - 16$