先化简 再求值 x分之x 2

题目有误吧(x-x)x-1分之4(x-x)+(x-2)再问：(x方-x)(x-2)方再答：

解:原式=(x-y)×(xy)分之(xy)的平方-(x-y)的平方乘以(x的平方×y的平方)分之(y的平方-x的平方)=-(xy分之4)当x=2根号3,y=2-根号3时;代入-(xy分之4),结果为5

你可以把这式子化简了挺简单的化简完就发现X都约掉啦式子是个定值所以X怎么变值都不变看错也没事什么公式?这题就得动笔算啊

小括号内先通分：分母为x平方-4,分子为3x平方+6x,另一个是x平方-2x化简：{x²-4分之2x²+8x}÷x²-4分之2x结果=x+4

原式=(x+1)²/(x+2)÷(x+1)(x-1)/(x-1)-x/(x+2)=(x+1)²/(x+2)÷(x+1)-x/(x+2)=(x+1)/(x+2)-x/(x+2)=(x

【先化简再求值】（x-1）分之x÷【(1-x分之1）-1-x】=（x-1）分之x÷（x^2/(1-x)）=-1/xx=1时,原式无意义,x=2时,原式=-1/2,x=0时,原式无意义【选择题】下列约分

原式=-x2-y2-3xy-x2+y2=-2x2-3xy，当x=-1，y=2时，原式=-2×（-1）2-3×（-1）×2=4．

x²+2x+1=10（x+1)²=10x+1=3或x+1=-3所以x=2或x=-4【（x²+4)/x-4】÷【（x²-4)/(x²+2x)】=【（x&

(x+y)/[1/(x^2+y^2)]/(x^4-y^4)=(x+y)(x^2+y^2)/[(x^2-y^2)(x^2+y^2)]=(x+y)/(x^2-y^2)=1/(x-y)=1/(8-11)=-

原式=(x-1)(x+1)/(x+2)*(x+2)/x-1=x+1然后代入数值即可很高兴为您解答,【学习宝典】团队为您答题.请点击下面的【选为满意回答】按钮,

(x^2-2x+1)/(x^2-1)+1/(x+1)=(x-1)^2/(x+1)(x-1)+1/(x+1)=(x-1)/(x+1)+1/(x+1)=x/(x+1)=1-根2分之一

x²-3x+2=0(x-1)(x-2)=0因为分母x-1≠0所以x-2=0x=2原式=x(x-1)/(x-1)*(x+1)(x-1)/(x-1)²=x*(x+1)/(x-1)=2*

{1-x/(x-1)}÷1/x(x-1)=(x-1-x)/(x-1)÷1/x(x-1)=-1/(x-1)÷1/x(x-1)=-x

[(x-4)/(x^2-1)]÷[(x^2-3x-4)/(x^2+2x+1)]+1/(x-1)=[(x-4)/(x-1)(x+1)]÷[(x+1)(x-4)/(x+1)^2]+1/(x-1)=[(x-

x2+y2+4x-8y+20=0(x+2)^2+(y-4)^2=0所以x=-2y=4(x-y)2(x+y)2-(x2+y2)2=(x^2-y^2)^2-(x^2+y^2)^2=2x^2*(-2y^2)

原式=(x+1)/(x+1)²×x(x-1)/[-2(x-1)]=-1/(x+1)×x/2=-x/2(x+1)当x=√2时原式=-√2/2(√2+1)=-√2(√2-1)/2=(√2-2)/

--2分之1(xy--x^2)+3(y^2--2分之1x^2)+2(4分之1xy--2分之1y^2)=--xy/2+x^2/2+3y^2--3x^2/2+xy/2--y^2=--x^2+2y^2,当x

原式=2x2-2xy-6x2+9xy-2x2+2x2-xy+y2=-2x2+5xy+2y2，当x=-1，y=-2时，原式=-2+10+8=16．

（x-2-x+2分之5）÷2x+4分之x-3=（x-2-x+5/2）÷2x＋x/4-3=1/2÷2x＋x/4-3=1/4x＋x/4-3