f(x)=(x-3)(3x+2)^3
f'(x)=(x-3)'(3x+2)^3+(x-3)[(3x+2)^3]'
=(3x+2)^3+(x-3)[3(3x+2)^2*3]
=(3x+2)^3+(x-3)[9(3x+2)^2]
=(3x+2)^2[(3x+2)+9(x-3)]
=(3x+2)^2(12x-25)
f(x)=(x-3)(3x+2)^3
f'(x)=(x-3)'(3x+2)^3+(x-3)[(3x+2)^3]'
=(3x+2)^3+(x-3)[3(3x+2)^2*3]
=(3x+2)^3+(x-3)[9(3x+2)^2]
=(3x+2)^2[(3x+2)+9(x-3)]
=(3x+2)^2(12x-25)