1+2+3+.+104+105=( )x( )

x^5+x^4 = (x^3-x)(x^2+x+1)+x^2+x 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 f(x-1)=x^2-2x+3(x (x+3)×(x+2)×(x+1)×x=3024 f(x)=(x-1)(x-2).(x-3)求导 (x+2)(x-3)(x-6)(x-1)=0 函数,y=3x/(x^2+x+1) ,x 函数y=3x/(x^2+x+1) （x 2x-(91-x)=1/3(91-x)-x 1/(x-4)(x-3)+1/(x-3)(x+2)+1/(x-2)(x-1)+1/(x-1)x+1/x(x+1)=1/x (2x-1)/(x-1)(x-2)=(x-5)/(x-2)(x-3) x/2x^2-11x-21=(x+7)/x^2-1