找错了,应为：
x^3-3x^2+4=x^3+1-3x^2+3
=(x^+1)(x^2-x+1)-3(x-1)(x+1)
=(x+1)(x^2-x+1-3x+3)
=(x+1)(x^2-4x+4)
=(x+1)(x-2)^2=0难道是我板书抄错了？=(x^+1)(x^2-x+1)-3(x-1)(x+1)这步是怎么来的？x^3+1=(x^2+1)(x^2-x+1)
x^3+1≠(x^+1)(x^2+x+1)这是公式吗？