Answer
$sin~495°=\frac{\sqrt 2}{2}$
$cos~495°=-\frac{\sqrt 2}{2}$
$tan~495°=-1$
Work Step by Step
Let $θ'$ be the reference angle. We must have that $0°\leqθ'\lt360°$
$θ'=θ=n·360°$, where $n$ is an integer.
$θ'=495°-360°=135°$
$sin~495°=sin~135°=\frac{\sqrt 2}{2}$
$cos~495°=cos~135°=-\frac{\sqrt 2}{2}$
$tan~495°=tan~135°=-1$
