Please can anyone help me with these questions

1. f (x) = 3 sin 3 (x - π/6) + 2


a. 2π

b. π/6

c. 2π/3

d. 3

e. π/3

f. 2



2. find cos2x, given that cos x = 4/7



a. 9/7

b. -17/49

c. 81/49

d. -6/7

e. -9/7



c. find sin 20, given sin 0 = 9/15



a. 24/15

b. 18/15

c. 216/225

d. 81/225