# How do you find the values of theta given costheta=1?

$\theta = 0 + 2 n \pi$
$\cos \theta = 1$
$\Rightarrow \theta = {\cos}^{-} 1 \left(1\right) = 0$
$\Rightarrow \theta = 0 + 2 n \pi \textcolor{w h i t e}{x} n \in \mathbb{Z}$