For this case we must find an expression equivalent to:
[tex]Sin (\frac {7 \pi} {6})[/tex]
According to the unit circle, [tex]\frac {7 \pi} {6}[/tex] is in the third quadrant and equals 210 degrees.
Then, we must find an expression equivalent to:
[tex]Sin (210) = - \frac {1} {2} = - 0.5[/tex]
We have to:
[tex]\frac{11 \pi} {6}[/tex]
It is in the fourth quadrant and is equivalent to 330 degrees, according to the unit circle.
[tex]Sin (330) = - \frac {1} {2} = - 0.5[/tex]
Answer:
Option D
