XYZ YZZ=532,其中XYZ是0到9的数.计算XYZ

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(1)先化简,再求值:[4(xy-1)²-(xy+2)(2-xy)]÷1/4xy,其中x=-2,y=1/5.

(1)[4(x²y²-2xy+1)-(2xy-x²y²+4-2xy)]÷1/4xy=(4x²y²-8xy+4-2xy+x²y

化简求值[(xy+2)(xy+2)-2(xy+1)+2]÷(xy),其中x=10,y=-25分之1

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

先化简再求值:2(xy^2-2y+1/2xy)-(xy+3xy^2-4y),其中x=4,y=1/2,

原式=2xy^2-4y+xy-xy-3xy^2+4y=-xy^2=-4×(1/2)^2=-1

先化简,再求值 ⒈2(Xy+Xy)-3(Xy-xy)-4Xy,其中X=1,y=-1

1.2(Xy+Xy)-3(Xy-xy)-4Xy=2*2xy-0-4xy=4xy-4xy=02.1/2ab-5aC-(3acb)+(3aC-4aC)=1/2ab-5ac-3acb-ac=1/2ab-6a

[(xy+2)(xy-2)-2x^2y^2+4]/xy,其中x=10,y=-1/25

[(xy+2)(xy-2)-2x2y2+4]÷(xy)=(x2y2-4-2x2y2+4)÷xy=-x2y2÷xy=-xy,当x=10,y=1/25时,原式=-2/5.

[(xy+2)(xy-2)-2x^2y^2+4]/(xy),其中:x=10,y=-1/25

[(xy+2)(xy-2)-2x^2y^2+4]/(xy)=[(x^2y^2-4)-2x^2y^2+4]/(xy)=-x^2y^2/xy=-xy=-10*(-1/25)=2/5

先化简,再求值:{(xy-2)^2+4xy-4}/(-xy),其中x=10.,y=-1/25

令t=xy方程变为:[(t-2)^2+4t-4]/(-t)=(t^2-4t+4+4t-4)/(-t)=-t=-xy又x=10,y=-1/25-xy=-10*(-1/25)=2/5

化简求值:[(xy-2)²+4xy-4]÷(xy),其中x=10,y=1/25

[(xy-2)²+4xy-4]÷(xy)=(x²y²-4xy+4+4xy-4)÷(xy)=x²y²÷xy=xy=10×1/25=2/5

(8xy-3x平方)-5xy-2(3xy-2x平方),其中,x=2,y=-1

(8xy-3x平方)-5xy-2(3xy-2x平方)=8xy-3x²-5xy-6xy+4x²=x²-3xy=4+6=10

3xy²-[xy-2(xy-3/2x²y)+3xy²]+3xy²,其中x=3,y

原式=3xy²-(xy-2xy+3x²y+3xy²)+3xy²=3xy²-(-xy+3x²y+3xy²)+3xy²=3x

[(2+xy)(xy-2)+(-xy-2)的平方]其中x=6,y=-3分之2

原式=x²y²-4+x²y²+4xy+4=2x²y²+4xy=2*36*4/9+4*6*(-2/3)=16

先化简,再求值:{(xy-2)^2+4xy-4}/(-xy),其中x=1.,y=-1/25

{(xy-2)^2+4xy-4}/(-xy)={(xy-2)^2+2(xy-2)+1+2xy-1}/(-xy)={[(xy-2)+1]^2+2xy-1}/(-xy)={(xy-1)^2+2xy-1}/

(x+2y-3xy)-(-2x-y+xy),其中x+y=1/2,xy=-1/2

(x+2y-3xy)-(-2x-y+xy)=x+2y-3xy+2x+y-xy=(1+2)x+(2+1)y-(3+1)xy=3x+3y-4xy=3(x+y)-4xy=3*1/2-4*(-1/2)=3/2

① 先化简,再求值.【2x(xy-xy)+xy(xy-x)】÷xy,其中x=2013,y=2012

你好.这个很简单的!(1)【2x(xy-xy)+xy(xy-x)】÷xy=2x(1-y/x)+xy(1/x-1/y)=x-y,当x=2013,y=2012时,x-y=1.(2)【2x(2x+3)-2x

4x的平方+3xy-x的平方-3xy+9,其中x=-2

4x的平方+3xy-x的平方-3xy+9=3x^2+9=3*(-2)^2+9=12+9=21

(x+2y-3xy)-(-2x-y+xy),其中x+y=,xy=-,求值.

3x-4xy+3y再问:然后的过程再答:再带入值等于3.5再答:马上再答:给你照片再答:再答:亲采纳哟

-3(2x-xy)-4(-6+xy+x.其中x=1,y=-1

-3(2x-xy)-4(-6+xy+x)=-6x+3xy+24-4xy-4x=-10x-xy+24=-10+1+24=15先化简.后代入求值

-xy(x的平方y的五次方-xy的三次方-y),其中xy的平方=2

原式=-x³y^6+x²y^4+xy²=-(xy²)³+(xy²)²+(xy²)=-2³+2²+2=

证明arctanx+arctany=arctan(x+y/1-xy),其中xy不等於1

左右2边取正切,左边=(X+Y)/(1-XY)=右边.左边=arctan[(X+Y)/(1-XY)+Z]/[1-(X+Y)Z/(1-XY)]=arctanc(X+Y+Z-XYZ)/[1-XY-(X+Y

[(xy-2)(-xy-2)-4(xy-1)^2]除以(-xy),其中x=20,y=-25分之1

[(xy-2)(-xy-2)-4(xy-1)^2]除以(-xy)=[-x²y²+4-4(x²y²-2xy+1)]÷(-xy)=(-x²y²+