Answer:
3√3
Step-by-step explanation:
If sinx = 4/8, find Cos (6x)
we need to first find cos
but applying trigonometry rule
sin²x+cos²x = 1
sinx = 4/8
sin²x = (4/8)² = 4²/8² = 16/64
from the rule
cos²x= 1 -sin²x = 1-16/64 = 64-16/64 = 48/64 = 3/4
cos²x = 3/4
cos x = √3/4 = √3/2
cos 6x = 6 x √3/2 = 3√3
