首先,有一则公式:若f(x)=uv,则f'(x)=u'v+uv'f(x)=x[(x+1)(x+2)]f'(x)=x'*[(x+1)(x+2)]+x*[(x+1)(x+2)]'=(x+1)(x+2)+x*[(x+1)'*(x+2)+(x+1)*(x+2)']=(x+1)(x+2)+x*[(x+2)+(x+1)]=(x+1)(x+2)+x(x+2)+x(x+1)f'(0)=(0+1)*(0+2)+0*(0+2)+0*(0+1)=1*2=2