1/1x2/1+2/1x3/1+3/1x4/1+4/1x5/1...+39/1x40/1怎么算还有过程

因式分解（1+x+x2+x3)2-x3 计算(x3+x2+x+2)/(x2+1) 2x3+3x2-4x-1 因式分解x3-x2-x-1 x3-x2-3x-1 化简 因式分解：x4+x3+2x2 +x+1 3-X2+X-1分之X4+X3-2乘以x3+2x2+2x+2分之X四次方-1除以-2分之X3-X-X2+1化简 1.证明（8-7x-6x2+x3）+(x3+5x2+4x-1)-(-x2-3x+2x3-3)的值与x无关.快, 求证:无论X取何值下列（8-7X-6X2+X3)+(X3+5X2+4X-1)-(-X2-3X+2X3-3)结果不变 x4+2x3+x2+1+2(x+x2)因式分解 x2-x-1=0,-x3+2x2+2008= 若 x2-3x+1=0,求（2x2×x3-5x2×x2+2 x3-8x2 ）÷（x2+1 ）的值 X3-X2+X-1分之X4+X3-2乘以x3+2x2+2x+2除以-2分之X3-X-X2+1化简 化简求值2X3+4X-1/3X2-(X+3X2-2X3) 其中X=-3 化简求值2X3+4X-1/3X2-(X+3X2-2X3) 其中X=-3 若点(x1,1),(x2,2),(x3,-3)都是反比例函数y=-1/x图象上的点,则( ) A.x1>x2>x3 B.x1>x3>x2C.x3>x2>x1 D.x3>x1>x2 已知x2+5x-4=0,求x3+6x2+x+2的值已知x2+x-1=0,求x3+2x2+3的值 [x3-3x2+( )-1]+[( )-6x2-2x+( )]=2x3+( )+2x+2是 3次 2次