Answer
$= \frac{4}{9}$
Work Step by Step
Recall, because of PEDMAS, we consider what is inside of parenthesis first, and then we consider the exponent. Thus, we obtain:
$= (\frac{1}{2} + \frac{1}{3} - \frac{1}{6})^{2}$
$=(\frac{3}{6} +\frac{2}{6}-\frac{1}{6})^{2}$
$= (\frac{5}{6} - \frac{1}{6})^{2}$
$= (\frac{5}{6} - \frac{1}{6})^{2}$
$= (\frac{4}{6})^{2}$
$= (\frac{2}{3})^{2}$
$= (\frac{4}{9})$