观察例题,然后回答例：x+1/x=3,则x^2+x^-2=?由x+1/x=3,得（x+1/x)^2=9,即x^2+x^-

观察例题,然后回答例：x+1/x=3,则x^2+x^-2=?由x+1/x=3,得（x+1/x)^2=9,即x^2+x^- x^5+x^4 = (x^3-x)(x^2+x+1)+x^2+x (观察下式:(x-1)(x+1)=x^2-1; (x-1)(x^2+x+1)=x^3-1; (x-1)(x^3+x^2+ 解方程x/(x-2)=2x/(x-3)+(1-x)/(x-5x+6) x^4+x^3+x^2+x+1=0,x^2006+x^2005+x^2004+x^2003+x^2002 y=(x-1)(x-2)(x-3)(x-4)(x-5)(x-6)(x-7)(x-8)(x-9)(x-10)的导数在x=1 设函数f(x)=(x-1)(x-2)(x-3)(x-4)(x-5)(x-6)(x-7)(x-8)(x-9)(x-10), x+2/x+3－x+1/x+2=x+8/x+9－x+7/x+8 （1） x-3/x-2 - x-5/x-4=x-7/x-6 - x-9/x-8 2x/x^2-9=x-1/x^2-6x+9-1/x+3 1.x/9+x=62.x/x+1 + x+1/2x = 3 (x-2)(x2-6x-9)-x(x-5)(x-3)其中x= -1/3