Question

Select all the correct answers.

Answer 1

Answer:

• The measure of reference angle is $30^{\circ}$.
• $\cos \theta=\frac{\sqrt{3}}{2}$

Step-by-step explanation:

Converting $\theta$ to degrees,

$\theta=\left(\frac{11\pi}{6} \right) \left(\frac{180}{\pi} \right)=330^{\circ}$

This means $\theta$ lies in Quadrant 4, and thus its reference angle is $360^{\circ}-330^{\circ}=\boxed{30^{\circ}}$

Since $\theta$ lies in the fourth quadrant, $\sin \theta$ and $\tan \theta$ are negative.

Since $\theta$ lies in the fourth quadrant, $\cos \theta$ is positive, and is equal to $\cos (30^{\circ})=\boxed{\frac{\sqrt{3}}{2}}$