x的平方-2x 1分之x的平方乘x 1分之x-1乘1 x分之1-x

上边的方程可以写成x^2=6-3x,这个方程有两个根：x1和x2.所以x1^2=6-3*x1,x2^2=6-3*x2所以让求的式子变成了：x2/(6-3*x1）+x1/(6-3*x2)然后通分：(15

〔(x-1)/(x+2)〕×〔(x^2-4)/(x^2-2x+1)〕÷(1/x^2)=〔(x-1)/(x+2)〕×〔(x+2)(x-2)/(x-1)^2〕×x^2＝〔(x^2)(x-1)(x+2)(x

原式=(x^2-1)/(x^2+2x)*(x-1)/x=(x-1)^2(x+1)/x^2(x+2),解不等式组：x+2>1,——》x>-1,2(x-1)>-6,——》x>-2,所以,解集为：x>-1,

前者分子：x^2-y^2=(x+y)(x-y)那前面这项就可以化简约分啦后者分子：4x^2-4xy+y^2=(2x)^2-2*2xy+y^2=(2x-y)^2建议你理解一下x^2-2xy+y^=(x-

(xy-x的平方）除以xy分之x的平方-2xy+y的平方乘x的平方分之x-y=x(y-x)*xy/(x-y)²*（x-y）/x²=-y再问：不好意思，打错了(xy-y的平方）除以x

再答：望采纳，谢谢

x的平方-9分之x的平方+2x-3乘x的平方-1分之x的平方-5x+6=(x-3)分之(x-1)乘[(x-1)(x+1)]分之(x-2)(x-3)=(x+1)分之(x-2)

原式=[(x+1)(x+2)/(x-1)(x-2)][-x(x-2)/3(x+1)]=-x(x-2)(x+1)(x+2)/[3(x-1)(x-2)(x+1)]=-x(x+2)/3(x-1)=-(x&s

=(x+y)(x-y)/(x+y-1)(x-y+1)×(x-y+1)(x-y-1)/(x+y)²×(x+2y)(x-y)/x(x-y)=(x-y-1)(x+2y)(x-y)/x(x+y-1)

先合并同类项得（a的平方-4）乘x的立方+（a+2）乘x的平方+x+1由于是关于x的2次多项式,x的立方项系数为0,所以a的平方-4=0,a=2或-2而且x的平方项系数不为0,则a+2不等于0,a不等

x的平方乘y的平方-4-2x的平方乘y的平方=-x的平方乘y的平方-4

原式=[(x+1)/(x-1)]-[(x²-2x)/(x²-1)]×[(x²+2x+1)/(x²-x-2)]=[(x+1)/(x-1)]-{x(x-2)/[(x

[(x^2-2x+1)/x^2]÷(x^2-1)*[(x^2+x)/(x^2-3x+2)]=[(x-1)^2/x^2]÷[(x+1)(x-1)]*[x(x+1)/(x-1)(x-2)]=(x-1)^2

原式=[(x+y)/(x-y)]^2*[2(x-y)/5(x+y)-[X/(x^2y^2)]/[x/(x+y)]=2/5-[x/(x^2y^2)]*[(X+y)/x]=2/5-(x^2y^2)/(x+

原式=1/(x+1)*[(x-3)/(x+3)^2+2/(x+3)]-x/(x+3)(x-3)=1/(x+1)[3(x+1)/(x+3)^2]-x/(x+3)(x-3)=3/(x+3)^2-x/(x+

(x-1)^2/(4x)×（2x^2)/(x-x^2)=(x-1)^2/(4x)×（2x^2)/[-x(x-1)]=-(x-1)/2=(1-x)/2

2x/9-7x²/27=16两边乘277x²-6x+432=0判别式=(-6)²-4×7×432

=(x+2)/(x-3)×(x-3)²/(x+2)(x-2)=(x-3)/(x-2)

=x²/(x²+4)×(x+2)/x(x-2)-1/(x-2)=x(x+2)/(x²+4)(x-2)-1/(x-2)=[x(x+2)-(x²+4)]/(x

X1+X2=-6/2=-3X1*X2=-3/21/X1+1/X2=(X1+X2)/(X1X2)=-3/(-3/2)=2