Question

if sin a =½ find 4 cos³ - 3 cos a​

Answer 1

Step-by-step explanation:

If sin a = 1 / 2

then a = 30°

4 cos³a - 3cosa

= cos³a

= ( sqrt 3 / 2 )³

= 3 sqrt 3 / 8

#answerwithquality #BAL