z=x

(x+y-z)(x-y+z)= z=x X+Y+Z=? x/y=(x+z)/(y+z)y/z=(x+y)/(x+z) 已知 x/(y+z)+y/(z+x)+z/(x+y)=1求 (x*x)/(y+z)+(y*y)/(x+z)+(z*z)/(x+y)=? z=x^(y/z) 偏导数 (y+z)/x=(z+x)/y=(x+y)/z求x+y-z/x+y+z的值 fangchengzu:X+Z=Y 7Z=X+Y+Z X+Y+Z=14 z+=x>y?++x: x+x+z+z+z=29,x+z=14,问x=几,z=几 (x-2y+z)(x+y-2z)分之（y-x)(z-x) + (x+y-2z)(y+z-2x)分之(z-y)(x-y) + (y+z-2z)(x-2y+z)分之（x-z)(y-z)=?第三部分那个是 （y+z-2x)(x-2y+z)分之（x-z)(y-z) 用行列式的性质证明：y+z z+x x+y x y z x+y y+z z+x =2 z x y z+x x+y y+z y z x 这个怎么证? 设z=z(x,y)由方程φ(x/z,y/z) 确定,证明x*∂z/∂x+y*∂z/∂y=z （x-y+z)(-x+y+z)=[z+( )][ ]=z²-（ ）² (x-y+z)(-x+y+z)=[z+( )][ ]=z的平方减( )的平方 z变换X(z)=1+z^2013-z^-2013,求x(2013) 已知(x+y)(x+z)=x,(y+z)(y+x)=2y,(z+x)(z+y)=3z,求x,y,z 若z分之x+y+z=y分之x-y+z=x分之-x+y+z,求xyz分之(x+y)(y+z)(z+x)