In right angled triangle ABC, if ∠A = 30°, find the value of 3 sin A - 4 sin3 A.
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 1.
3 sin A - 4 sin3 A
= 3 sin 30° - 4 (sin 30°)3
= 3(1/2) - 4(1/2)3
= 3/2 - 4(1/8)
= 3/2 - 1/2
= 1