What is [tex]\tan \left(\frac{11 \pi}{6}\right)[/tex]?

A. [tex]-\sqrt{3}[/tex]

B. [tex]\sqrt{3}[/tex]

C. [tex]-\frac{\sqrt{3}}{3}[/tex]

D. [tex]\frac{\sqrt{3}}{3}[/tex]



Answer :

To determine [tex]\(\tan \left(\frac{11 \pi}{6}\right)\)[/tex], let's analyze the angle [tex]\(\frac{11\pi}{6}\)[/tex] in the context of the unit circle.

1. Convert the Angle to Degrees:
[tex]\[ \frac{11\pi}{6} \text{ radians} \times \frac{180^\circ}{\pi} = \frac{11 \times 180^\circ}{6 \times 1} = 330^\circ \][/tex]
So, [tex]\(\frac{11\pi}{6}\)[/tex] radians is equivalent to [tex]\(330^\circ\)[/tex].

2. Determine the Reference Angle:
Since [tex]\(330^\circ\)[/tex] is in the fourth quadrant, we find the reference angle by subtracting [tex]\(330^\circ\)[/tex] from [tex]\(360^\circ\)[/tex]:
[tex]\[ 360^\circ - 330^\circ = 30^\circ \][/tex]
Therefore, the reference angle is [tex]\(30^\circ\)[/tex].

3. Find Tangent of the Reference Angle:
We know from trigonometric ratios that:
[tex]\[ \tan(30^\circ) = \frac{\sqrt{3}}{3} \][/tex]

4. Determine the Sign:
The angle [tex]\(330^\circ\)[/tex] is in the fourth quadrant, where the tangent function is negative. Therefore, we have:
[tex]\[ \tan(330^\circ) = -\tan(30^\circ) = -\frac{\sqrt{3}}{3} \][/tex]

So, the value of [tex]\(\tan \left(\frac{11 \pi}{6}\right)\)[/tex] is:
[tex]\[ -\frac{\sqrt{3}}{3} \][/tex]

Therefore, the correct answer is:
C. [tex]\(-\frac{\sqrt{3}}{3}\)[/tex]