x²+y²=2z及z=2

用行列式的性质证明：y+zz+xx+yxyzx+yy+zz+x=2zxyz+xx+yy+zyzx这个怎么证?利用行列式加法定则,左边可以展开为四个单字母行列式,然后调换行顺序,合并之,可得右式.

如果2^x=5^y=10^z,试以x及y表示zxlg2=ylg5=z

已知(x+y)(x+z)=x,(y+z)(y+x)=2y,(z+x)(z+y)=3z,求x,y,z显然x=y=z=0是一解.若x,y,z中有两数互为相反数,设为x,y(因为下面的过程忽略系数的影响,是对称的)则由1,2两式得到x=y=0,则

已知：4x-5y+2z=0x+4y-3z=0则：(x*x+y*y+z*z)/(x*y+y*z+z*x)=____.4x-5y+2z=0（1）x+4y-3z=0（2）（2）×4-（1）得21y=14z即y=2z/3代入（2）得x=z/3∴z=

已知实数xyz满足x/y+z+y/z+x+z/x+y=1求x^2/y+z+y^2/z+x+z^2/x+y的值纠正下！：已知实数xyz满足（x/y+z）+（y/z+x）+（z/x+y）=1求（x^2/y+z）+（y^2/z+x）+（z^2/x

试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y)有这样的公式：a^3+b^3+c^2-3abc=(a+b+c)(a^2+b^2+c^2-ab-bc-ca)左边减右边,证明：（x+

x^2(y+z)^2-2xy(x-z)(y+z)+y^2(x-z)^2=[x(y+z)-y(x-z)]^2=(xz+yz)^2=z^2(x+y)^2x²(y+z)²-2xy(x-z)(y+z)+y²(x-z)&

x^2/(z+y)+y^2/(x+z)+z^2/(x+y)=0,求x/(z+y)+y/(x+z)+z/(x+y)的值令P=待求值计算得xp+yp+zp=(x^2/z+y)+(y^2/x+z)+(z^2/x+y)+x+y+z=0+x+y+z=

X/(Y-Z)+Y/(Z-X)+Z/(X-Y)=0求证X/(Y-Z)^2+Y/(Z-X)^2+Z/(X-Y)^2=0通过上面求证下面^2是……的2次方X/(Y-Z)^2+Y/(Z-X)^2+Z/(X-Y)^2=0X/(Y-Z)=-Y/(Z-

线性代数初级问题证明|y+zz+xx+y||xyz||x+yy+zz+x|=2|zxy||z+xx+yy+z||yzx|为什么直接用r1-r2-r3;r2-r1-r3;r3-r1-r2得|-2x-2y-2z||-2z-2x-2y||-2y-

∫∫e^z/√(x^2+y^2)dxdy,∑为锥面,z=√(x^2+y^2)及平面z=1,z=2所围的立体表面的外侧.如图.∫∫∑e^z/√(x^2+y^2)dxdyə[e^z/√(x^2+y^2)]/əz=e^z/√(

求∫∫∫z√（x^2+y^2+z^2)dxdydz,其中D是由球面x^2+y^2+z^2《=1及z>=√3√（x^2+y^2)所围成的闭区域先求球面与圆锥面的交线：x²+y²+z²=1与z=√3√（x²

(x+y-z)^2-(x-y+z)^2=?根据公式(a+b+c)^2=a^2+b^2+c^2+2ab+2bc+2ac公式展开：得到(x^2+y^2+z^2=2xy-2yz-2xz)-(x^2+y^2+z^2-2xy-2yz+2xz)合并同类

(x-y-z)*()=x^2-(y+z)^2填空(x-y-z)*(x+y+z)=x^2-(y+z)^2（x-y-z）×（x+y+z）=x²-（y+z）²希望对你有帮助，满意请及时采纳，你的采纳是我回答的动力！

已知x+y+z=3,x^2+y^2+z^2=29,x^3+y^3+z^3=45.求xyz及x^4+y^4+z^4需要用到因式分解x^3+y^3+z^3-3xyz=(x+y+z)(x^2+y^2+z^2-xy-yz-xz)分解过程参见：htt

分解因式:f(x,y,z)=x^2(y-z)+y^2(z-x)+z^2(x-y)=x²(y-z)+y²(z-x)+z²(x-z+z-y)=(y-z)(x²-z²)+(z-x)(y²

证明：x/(y+z)+y/(z+x)+z/(x+y)>=3/2其中x,y,z>0x/(y+z)+y/(x+z)+z/(x+y)>=3/2设S=x+y+zx/(y+z)+y/(x+z)+z/(x+y)=S/(y+z)+S/(x+z)+S/(x

已知实数x.y.z满足x+y=5及z的2次方=xy+y-9则x+2y+3z=?x=5-yz2=(5-y)y+y-9=6y-y2-9=-(9-6y+y2)=-(y-3)2由题意,只有当该项为0时等式成立得y=3那么z=0x=2即原式=2+6+

x+2y=3x+2z=4y+z求x:y:zx+2y=3x+2z得y=x+z代入x+2y=4y+z得x+2x+2z=4x+4z+zx=-3z代入y=x+z得y=-3z+z=-2zx:y:z=-3z:-2z:z=-3:-2:1设x+2y=3x+

x+y/2=z+x/3=y+z/4x+y+z=27x+y/2=z+x/3=y+z/4①x+y+z=27②①×12得：12x+6y=12z+4x=12y+3z故：12x+6y=12z+4x③12z+4x=12y+3z④由③得x=（6z-3y）