Question

If sin ϴ = 1/2 , Find the value of 3cos ϴ - 4 cos ^3 ϴ​

Answer 1

Answer:

Let theta be ₹.

sin ₹ = 1/2

sin ₹ = sin 30°

₹ = 30°

to prove:-

3cos₹ - 4cos^3₹ = 0

3cos30° - 4cos^3 30° = 0

3( \sqrt{3} /2) - 4( \sqrt{3} /2)^{3} = 03( 3 2)−4( 3/2)3 =0

0 = 0

Hence Proved

Answer 2

Answer:

3cos ϴ - 4 cos ^3 ϴ = 0

Step-by-step explanation:

Sin ϴ = 1/2

Sin inverse (1/2) = 30°

There for,

3cos(30) - 4cos^3 (30) = 3(root3÷2) - 4(3root3÷8)

= 0