先化简,再求值:根号12xy的平方-搜答案-智慧作业帮

原式=2x³y-2x²y²+x²y²-x³y=x³y-x²y²=x²y(x-y)=2011²

原式=2xy+x+3x(x−1)÷y(x2+2x−3)(x−1)2=2xy+x+3x(x−1)•(x−1)2y(x−1)(x+3)=3xy，当x=2+3，y=2-3时，原式=1(2+3)(2−3)=1

xy=1x^2+y^2=6x+y=2sqr（2)y-x=2注意后面那个分数是等于-1.最后强算就是了,最后那个分母有理化稍微有点复杂,我就不算了.

=2y√(3x)-x^2√(3x)-y^2√(3x)+15xy√(3x)=(2y-x^2-y^2+15xy)√(3x)=(4-9-4+90)*3=243

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

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

原式=-3x³y³+6x^4y^4+4x²y³*2x²y=-3x³y³+6x^4y^4+8x^4y^4=-3x³y&su

|x-2|²+(y-3)²=0x-2=0,y-3=0x=2,y=3原式=3xy-[2x-2xy-(3x+xy)-5y]=3xy-(2x-2xy-3x-xy-5y)=3xy-2x+2

(x+根号xy)/(y+根号xy)+((根号xy)-y)/(x-根号xy),=√x(√x+√y)/√y(√x+√y)+√y(√x-√y)/√x(√x-√y)=√x/√y+√y/√x=(x+y)/√xy

根号12xy^2-根号3x^5+b^2-y根号3xy^2+5x根号48x^2y=2y根号(3x)-x^2根号(3x)+b^2-y^2根号(3x)+20x^2根号(3y)=(2y-x^2-y^2)根号(

x+y=2√3x-y=4原式=[(x+y)-(x-y)]/(x-y)(x+y)×(x+y)²/2y=2y/(x-y)(x+y)×(x+y)²/2y=(x+y)/(x-y)=2√3×

15乘以X的平方加9(4x)^2+3xy-x^2-3xy+9=16(x^2)-(x^2)+9=15(x^2)+9再问：先化简，在求值，同学，我要过程！

[x＋√(xy)]／[√(xy)＋y]＋[√(xy)－y]/[x－√(xy)]=[x＋√(xy)]*[√(xy)-y]/(xy-y²)＋[√(xy)－y]*[x+√(xy)]/(x²

/>原式=[(x²-2xy+y²)/(x²-xy)]÷(x/y-y/x)={(x-y)²/[x(x-y)]}÷[(x²-y²)/(xy)]=

原式=(3y-xy)/(x^2-3x)=y(3-x)/x(x-3)=-y/x把x=根号2,y=-2代入原式=-(-2)/√2=√2

原式=3x2y-[2xy-2xy+3x2y+xy]，=3x2y-3x2y-xy，=-xy，当x=3，y=-13时，原式=-3×（-13）=1．

写出来,是两个分式的和然后左边分式分子分母同除以（根号X加根号Y）右边分式分子分母同除以（根号X减根号Y）化得原式等于（根号Y）分之（根号X）加上（根号X）分之(根号Y)通分,加起来,等于（根号XY）

2(xy-5xy的平方)-(3xy的平方-xy)＝2xy-10xy的平方-3xy的平方＋xy＝3xy-13xy的平方当x=-1,y=1时,原式＝-3＋13＝10

化简的结果是xy(x-2y)再问：过程？！再答：过程太麻烦了，电脑没法打。