# How do you simplify sqrt(16cos^2t-16sin^2t)?

simplify: $\sqrt{16 {\cos}^{2} t - 16 {\sin}^{2} t}$
$= 4 \sqrt{{\cos}^{2} t - {\sin}^{2} t} = 4 \sqrt{{\cos}^{2} 2 t} = 4 \cos 2 t$