神马作文网化简或计算 √20x^2y^2 z^5(x≥0,y≥0)
来源：学生作业帮助网 编辑：作业帮 时间：2024/11/18 01:54:13
∑是循环和例如∑a=a+b+c∑a^2=a^2+b^2+c^2∑(z-y)(x-y)/(x+y-2z)(y+z-2x)＝∑(z-y)(x-y)(x+z-2y)/(x+y-2z)(y+z-2x)(x+z
1/2(x+y+z)的平方+1/2(x-y-z)(x-y+z)-z(x+y)=½(x²+y²+z²+2xy+2xz+2yz)+½(x²-2x
（x+2y-3z）（x-2y+3z）=[x+(2y-3z)][x-(2y-3z)]=x²-(2y-3z)²=x²-(4y²-12yz+9z²)=x&#
/>#include<iostream>usingnamespacestd;intmain(){intx(2),y(3),z(4);z+=x++||y++||++z;cout<<
=[2X+(Y-Z)][2X-(Y-Z)]=4X^2-(Y-Z)^2=4X^2-Y^2-Z^2+2YZ^2表示平方不知道对不对
∵x-2y+z=（x-y）-（y-z）,x+y-2z=（y-z）-（z-x）,y+z-2x=（z-x）-（x-y）．设x-y=a,y-z=b,z-x=c,则原式=-ac/(a-b)(b-c)+(-ba
正整数?取对数即证：2xlnx+2ylny+2zlnz>(y+z)lnx+(x+z)lny+(x+y)lnzx>y>z,lnx>lny>lnz由排序不等式得xlnx+ylny+zlnz>ylnx+zl
(2x-y+z)(2x+y-z)=4x^2-(y-z)^2=4x^2-y^2-z^2+2yz
10再答：x=2.y=-3.z=2所以2+3+5=10再问：再答：那个给点给点财富值吗
球体体积3/4*pi*R^3三重积分用球坐标也可以,被积函数是1三重积分柱坐标被积函数是2*（根号下R^2-x^2-y^2）二重积分也可以,被积函数是2*（根号下R^2-x^2-y^2）..
(x-y+z)的2次方=(x-y)²+2z(x-y)+z²=x²-2xy+y²+2xz-2yz+z²
（x+2y-3z)^2+（x-2y+3z)(x+2y-3z)=（x+2y-3z)[(x+2y-3z)+（x-2y+3z)]=（x+2y-3z)(2x)=2x（x+2y-3z)
（-3x³y/2z²)²=（-3x³y)²/（2z²)²=9x的6次方y²/4z的4次方
(x+2y+3z)-(3x+2y-z)+(2x-3y+4z)=x+2y+3z-3x-2y+z+2x-3y+4z=-3y+8z
化简计算（4y+3x-5z)(3x-4y+5z)=[3x+(4y-5z)][3x-(4y-5z)]=9x^2-(4y-5z)^2=9x^2-16y^2+40yz-25z^2
1题设y-z=a,z-x=b,x-y=c,则a+b+c=0,y+z-2x=b-cx+z-2y=c-ax+y-2z=a-b于是原式=（y+z-2x)^2+(z+x-2y)^2+(x+y-2z)^2=(b
(x－2y+z)(-x+2y+z)＝〔z+(x-2y)][z-(x-2y]=z^2-(x-2y)^2=z^2-(x^2-4xy+4y^2)=z^2-x^2+4xy-4y^2
应用平方差公式a^2-b^2=(a+b)(a-b)(x+y+z)(x+y-z)(x-y+z)(-x+y+z)=[(x+y)^2-z^2][z^2-(x-y)^2]=-z^4+[(x+y)^2+(x-y
3x-2y-[-4x+(z+3y)]=3x-2y-(-4x+z+3y)=3x-2y+4x-z-3y=7x-5y-z