Answer
The statement does not make sense.
Work Step by Step
From the property of the cosine function,
$\cos \left( -\theta \right)=\cos \theta $
The value of $\cos \frac{\pi }{6}$ is
$\cos \frac{\pi }{6}=\frac{\sqrt{3}}{2}$
Thus, the value of $\cos \left( -\frac{\pi }{6} \right)$ is $\frac{\sqrt{3}}{2}$. So, the statement is false.
