Answer
False
Work Step by Step
$\cos$(2 * 45$^{\circ}$) = 2$\cos$ 45$^{\circ}$
First evaluate the value of each trigonometric statement:
$\cos$ (2 * 45$^{\circ}$) = $\cos$ 90$^{\circ}$ = 0
$\cos$ 45$^{\circ}$ = $\frac{\sqrt2}{2}$
Next evaluate each side of the equation:
$\tan$( 90$^{\circ}$) = 0
2 $\cos$ 45$^{\circ}$ = 2($\frac{\sqrt2}{2}$)
= $\sqrt2$
Therefore:
$\cos$(2 * 45$^{\circ}$) = 2$\cos$ 45$^{\circ}$ is a false statement.
