Question

find the value 3Sin20- 4sin^3 20​

Answer 1

Answer:

$sin(3x) \ = \ 3sinx \ -4sin^{3}x\\x=20 \ degree\\sin(60) = \ 3sin20 \ -4sin^{3}20\\3sin20 \ -4sin^{3}20 = \sqrt{3}/2$.