Please solve as soon as possible

Show that sin *0 = - -7 COS (20) + - cos (40) Which of the following four statements establishes the identity? O A. 1 + cos (20) sin *0 = [ sin zo) 7 = 2 8 5 Cos (20) + - cos (40) O B. 1 - cos (20) 2 B sin *o= [ sin 20) 7 - 2 cos (20) + - cos (40) OC sin *0= ( sin 20) 7 1 + cos (20) 2 8 5 COS (20) + - cos (40) OD. sin *0= ( sin 20) = =- 1 - cos (20) 1 2 8 5 Cos (20) + - cos (40)