Question

Which of the following expressions is equal to sin⁡⁡(-150°)?

Answer 1

The answer is -sin(30°)
You can use calculator if you want to verify or to compare values if equal.

Answer 2

Answer:

$sin (-150^{\circ})$=$-sin30^{\circ}$

Step-by-step explanation:

Given : $sin (-150^{\circ})$

To Find: Which of the following expressions is equal to $sin (-150^{\circ})$

Solution:

Property : $sin(-x)=sinx$

So, $sin (-150^{\circ})=-sin 150^{\circ}$

Now using identity : $sin x = sin (180-x)$

So, $-sin 150^{\circ} = -sin(180^{\circ}-150^{\circ})$

$-sin 150^{\circ} = -sin30^{\circ}$

Thus Option C is correct.

Hence $sin (-150^{\circ})$=$-sin30^{\circ}$