Answer
The function is neither even nor odd.
Work Step by Step
$f(-x) = \sin{(-x)} + \cos{(-x)}$
$\because \sin{(-x)} = - \sin{x} \hspace{10pt} \& \cos{(-x)} = \cos{x}$
$\therefore f(-x) = -\sin{x} + \cos{x} \neq f(x) \text{ or} -f(x)$
The function is neither even nor odd.
