求曲线x^2+y^2+z^2=6,z^2+y^2-x^2=4,在点（1,1,2）处的切线方程及法平面

已知x、y、z满足方程组：x+y-z=6；y+z-x=2；z+x-y=0 求x、y、z的值 已知X.Y.Z满足方程组,X+y-Z=6y+z-x=2z+x-y=0求X.Y.Z的值 已知：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. 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 已知(x+y)(x+z)=x,(y+z)(y+x)=2y,(z+x)(z+y)=3z,求x,y,z 已知x,y,z满足方程组｛x+y-z=6{y+z-x=2{z+x_y=0,求x,y,z的值 如果|x+y+z-6|+|2x+3y-z-12|+|2x-y-z|=0求x,y, x+2y=3x+2z=4y+z 求x:y:z (x*x+2)(y*y+4)(z*z+8)=64xyz,求x,y,z 求Y(Z)=Z(Z+2)/(3Z-7)(Z+1)的z反变换 求曲线x^2+y^2+z^2=9 y=x 参数方程 求曲线x^2+y^2+z^2=9 y=x 参数方程 若x+y=6,xy=-8,求代数式(x+y-z)^2+(x+y-z)(x+y+z)-2·z(x-y) 若x-y=6,xy=-8,求代数式(x+y+z)²+(x-y-z)(x-y+z)-2·z(x+y)的值 若|x+3|+|y-2|+|2×z+1|=0求(x×z-y×z)(y-x+z)的值 x=y/z=z/3,x+y+z ＝12,求2x+3y+4z是多少, 求适合方程组 3x+2y-z=4 2x-y+2z=6 x+y+z 已知x+y+z=6,x^2+y^2+z^2=12,求x,y,z的值