Evaluate the sine of the angle without using a calculator.
$150 ^ { \circ }$
A) $\frac { \sqrt { 2 } } { 2 }$
B) $- \frac { \sqrt { 2 } } { 2 }$
C) $\frac { \sqrt { 3 } } { 2 }$
D) $\frac { 1 } { 2 }$
E) 0

Question

Quizplus · Accepted Answer

The sine of $150^\circ$ can be found using the unit circle or sine function properties. $150^\circ$ is in the second quadrant where sine values are positive. Since $150^\circ = 180^\circ - 30^\circ$, using the reference angle of $30^\circ$, $\sin(150^\circ) = \sin(30^\circ) = \frac{1}{2}$.

Evaluate the Sine of the Angle Without Using a Calculator 150∘150 ^ { \circ }150∘

Evaluate the Sine of the Angle Without Using a Calculator $150 ^ { \circ }$