Question

Тригонометрия, не могу решить, прошу помощи!

Answer 1

1
sin(60-a)=sin60*cosa-cos60*sina=√3/2*cosa-1/2*sina
2
cos(a+120)=cosacos120-sinasin120=-1/2*cosa-√3/2*sina
3
sin(a+π/6)=sinacosπ/6+cosasinπ/6=√3/2*sina+1/2*cosa
4
cos(a-π/3)=cosacosπ/3+sinasinπ/3=1/2*cosa+√3/2*sina