由题意,f(x)=a(x-x1)(x-x2)(x-x3)则f'(x)=a(x-x2)(x-x3)+a(x-x1)(x-x3)+a(x-x1)(x-x2)令S=a(x1-x2)(x1-x3)(x2-x3)k1=f'(x1)=a(x1-x2)(x1-x3)=S/(x2-x3)k2=f'(x2)=a(x2-x1)(x2-x3)=S/(x3-x1)k3=f'(x3)=a(x3-x1)(x3-x2...