f(x)=e^(3x-1)×cos(2πx+π/3),
f'(x)=e^(3x-1)*(3x-1)'cos(2πx+π/3)-e^(3x-1)*sin(2πx+π/3)*(2πx+π/3)'
=3e^(3x-1)*cos(2πx+π/3)-2π*e^(3x-1)*sin(2πx+π/3)
=e^(3x-1)*[3cos(2πx+π/3)-2π*sin(2πx+π/3)]