5x2-(x-2)(3x+1)-2(x+1)(x-5)
5x2-(x-2)(3x+1)-2(x+1)(x-5)
(-2x2+3x)-[5x-(2x2+1)-x2].
(x-6)(x2+x+1)-x(2x+1)(3x-1)
解一元二次方程,3x2+1=6x,4x2+5x=81,x(x+5)=0,(2x-2)(x-1)=0,x(x+5)=5x-
因式分解:1.(x2+x-6)(x2+x-8)-242.(x+1)(x-2)(x-3)(x-6)+203.(x+1)(x
(x2+5x+4)2+2(x2+5x+4)2+1=(x2+.
分式计算:2x/x2-x-2÷(1-x/x+1)-x2+2x/x2-4
证明:(x3+5x2+4x-1)-(-x2-3x+2x3-3)+(8-7x-6x2+x3)的值与x无关.
解方程 x(x-6)+2x(x-3)=3(x2-x-1) 解不等式:2x2(x-3)+4(x2-x)≥x(2x2-2x+
化简求值;(3x+1)+(2x2+5x-1)-3x2,其中x=10
已知x2+3x-1=0,求(x+2)(x-2)+(x-1)2-x(x-5)的值.
已知x2-x-1=0,求(x+2)(x-2)+(x-3)2-x(x-5)的值.