Помогите 26, вроде не трудное, но я не знаю

1) f(x) = cos(π/2 - x/3) = sin(x/3) F(x) = -3cos(x/3) + C     -      B) 2) f(x) = sin(π/2 - x/3) = cos(x/3) F(x) = 3sin(x/3) + C     -      Д) 3) f(x) = sin(3π/2 - 3x) = -cos(3x) F(x) = -sin(3x)/3 + C     -       Г) 4) f(x) = cos(3π/2 - 3x) = -sin(3x) F(x) = cos(3x)/3 + C     -       Б)