1.x^2-3x-18=0 2.x^2+3x-5=0 3.x^2-4x-7=0 4.3^2-6x-9=0 5.3x^2-6x-9=0不解方程求：x1+x2=...x1乘以x2=...1/x1+1/x2=...x1^2+x2^2=...（x1-x2）^2=.

1.(x*2-3x+3)/(x*2-3x+2)-(x*2-5x+7)/(x*2-5x+6)-1/(x*2-4x+3)2.1/x(x+1)+2/(x+1)(x+3)+3/(x+3)(x+6) 3.已知：x*2-3x+1=0,求x*2+1/x*2. 一个“整式的乘法”的问题请先阅读下列解题过程,再仿做下面的问题.已知X*X + X - 1=0,求X*X*X + 2*X*X + 3的值.解X*X*X + 2X*X +3=X*X*X +X*X -X +X*X +X +3=X{X*X +X -1} +X*X +X -1 +4=0+0+4=4+ x + X*X + X*X*X=0.+ X*X + X*X*X 1.x²-2x-3 2.x²-5x-6 3.x²-9x-10 4.x²-9x-10 5.x²-2x-8 6.x²+2x-8 7.x²-x-12 8.x²+x-12 9.x²+6x-16 10.x²-14x-32 11.x²+7x-18 x^4+x^3+x^2+x+1=0,x^2006+x^2005+x^2004+x^2003+x^2002 1.lim x->∞ （2x/x^2+1)*cosx 2..lim x->∞{ [(x^2-x)arctanx]/x^3-x-5}3..lim x->0 （e^x-e^-x-2x)/(x-sinx) 4..lim x->0 (sinx-x)/(x^3) 5..lim x->0 (x^2*tanx)/(x-tanx) 6..lim x->0 (1+3/x)^2x 7..lim x->0 (1+2x)^(3/sinx) 8.lim x->∞ (x/1+x)^(x-3) 9..li 1.已知x²+2x=2,求x³+4x²+2x-6的值 2.已知x²+x-3=0,求x^4+2x³-x²-2x-2的值 1.解方程：2X/2X-1+X/X-2=2 2.解方程：2/X*X-X+3/X*X-4X*X-1=0 分式方程1.(3/x^2+2x)-(1/x^2-2x)=0 2.(x/x-3)=(x^1/x-1) 3.(x-3/x-2)+1=(3/2-x) 4.(2x+1/x^2+x)=(5/6x+6)5.3/2-1/3x-1=5/6x-2 x+(x+3)+2x+(2x-18)=255 (x-2)(x-4)+4x(x-3)=0 (x+2)(x-3)(x-6)(x-1)=0 已知1+x+x^2+x^3=0,求x+x^2+x^3+x^4+x^+x^6+x^7+x^8的值 如果1+x+x^2+x^3=0,求x+x^2+X^3+x^4+x^5+x^6+x^7+x^8的值, 已知x=2π+1.求(X-1)+(X-2)+(X-3)+(X-4)+(X-5)+(X-6)+(X-7)+(X-8)+(X-9)+(X-10) X^2-3X-2=0,求( x - 2x-1/x )÷(x-1)/(x^2-2x) 1/(x*x-2x-3)+2/(x*-x-6)+3/(x*x+3x+2)=0 已知X^2-X-1=0,则-X^3+2X+2006X^*X为什么=X^2+X X^3-7X^2+18X-24=0