Answer:sin(150°) = 1/2Step-by-step explanation:* Lets study how we can solve this problem- At first the measure of the angle is 150°- Ask your self in which quadrant can you find this measure* To know the answer lets revise the four quadrants# First quadrant the measure of all angles is between 0° and 90° the measure of any angle is α∴ All the angles are acute ∴ All the trigonometry functions of α are positive# Second quadrant the measure of all angles is between 90° and 180° the measure of any angle is 180° - α∴ All the angles are obtuse∴ The value of sin(180° - α) only is positive ⇒ sin(180° - α) = sinα# Third quadrant the measure of all angles is between 180° and 270° the measure of any angle is 180° + α∴ All the angles are reflex∴ The value of tan(180° + α) only is positive ⇒ tan(180° + α) = tanα# Fourth quadrant the measure of all angles is between 270° and 360° the measure of any angle is 360° - α∴ All the angles are reflex∴ The value of cos(360° - α) only is positive ⇒ cos(360° - α) = cosα* Now lets check the angle of measure 150- It is an obtuse angle∴ It is in the second quadrant∴ the value of sin(150) is positive ∴ sin(150°) = sinα∵ 180 - α = 150 ⇒ isolate α∵ α = 180° - 150° = 30°∴ sin(150°) = sin(30°)∵ sin(30°) = 1/2∴ sin(150°) = 1/2