先化简再求值(x减x分之一)除于x分之x加一-搜答案-智慧作业帮

y(x+y)+(x+y)(x-y)-x²=(x+y)(x-y+y)-x²=(x+y)x-x²=x²+xy-x²=xy=-4×4分之一=-1

4分之一（-4x^2+2x-8)-(2分之一x-1)=1/4*（-4*1/4+2*1/2-8）-（1/2*1/2-1）=1/4*（-8）-（-3/4）=-2+3/4=-5/4

化简得X分之一.可代入X=1求得原式=1再问：能把过程给我写出来吗?麻烦了再答：

原式=【x(x+1)-x】/(x+1)÷【x²-1+1】/(x²-1)=x²/(x+1)÷x²/(x+1)(x-1)=x-1代入x=1原式=1-1=0如果本题有

=(x²-x-x)/(x+1)÷(x²-1+1)/(x+1)(x-1)=x(x-2)/(x+1)×(x+1)(x-1)/x²=(x-2)(x+1)/x取x=2则原式=0

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

(x分之X的平方+4-4)除的X平方+2x分之X的平方-4=[(x²+4)/x-4]÷[(x²-4)/(x²+2x)]=[(x²-4x+4)/x]÷[(x+2)

您好：原式=[x/(x-1)²-1/(x-1)]*（x²-1）/2=1/2[x/(x-1)²-1/(x-1)]*(x+1)(x-1)=1/2[x(x+1)/(x-1)-(

1/X-1/Y=2可得Y-X/XY=2则Y-X=2YX所以（2X-10YX-2Y）/（X-2YX-Y）=（-14XY）/-4YX=7/2

9x-[3x-2(2y-x)]-(2x-3y+2)=9x-3x+2(2y-x)-2x+3y-2=4x+2(2y-x)+3y-2=4x+4y-2x+3y-2=2x+7y-2

3x-3/x平方-1除3x/x+1减1/x-1=3(x-1)/[(x-1)(x+1)]*(x+1)/3x-1/(x-1)=1/x-1/(x-1)=1/2-1=-1/2

[x+1-15/(x-1)]÷[(x^2-4x)/(x^2-x)]=[(x^2-1-15)/(x-1)]÷[x(x-4)/x(x-1)]=[(x^2-16)/(x-1)]÷[(x-4)/(x-1)]=

再问：很详细，已经看懂了非常感谢！可以再请教一道分解因式的题吗？3x的立方减18x的平方加27x再答：

(1)[1/(x-1)-1/(x+1)]*(x^2-1)/x=[x+1-(x-1)]/[(x-1)(x+1)]*(x^2-1)/x=[2/(x^2-1)]*[(x^2-1)/x]=2/x根据x=√5,

√(x-1)-√(1-x)=(x+y)²要使根号有意义x-1≥0且1-x≥0得x≥1且x≤1∴x=1∴0-0=（1+y)²y=-1x=1y=-1代入所求的式子2x分之一减x-y分之

因为(x-1/x)÷（x+1）/x=（x+1）（x-1)/x×x/（x+1）=x-1.所以当x=根2+1时,原式=根2..

(x-x-4\x-3)除(x的平方-4\x-3)=[x(x-3)-(x-4)]／﹙x-3﹚÷﹙x+2﹚﹙x-2﹚／﹙x-3﹚=﹙x²-4x+4﹚／﹙x-3﹚*﹙x-3﹚／﹙x+2﹚﹙x-2﹚

1/(x-3)+6/(9-x^2)=1/(x-3)+6/(3-x)(3+x)=(x+3-6)/(x-3)(x+3)=1/(x+3)=1/(-2)=-1/2

原式=(x²-4y²-x²-4xy-4y²)×(2/y)=(-8y²-4xy)×(2/y)=-16y-8x=-4+8=4