应该是X^4-4X^3+10X^2-12X+9吧x^4-4x^3+10x^2-12x+9=(x^4-4x^3+6x^2-4x+1)+(4x^2-8x+4)+4 =(x-1)^4+4(x-1)^2+4=[(x-1)^2+2]^2>=4 所以X^4-4X^3+10X^2-12X+9的最小值是4
