求f(x,y,z)=2x+y+3z在椭圆x^2+y^2=2,x+z=1的最大最小值

求f(x,y,z)=2x+y+3z在椭圆x^2+y^2=2,x+z=1的最大最小值 已知(x+y)(x+z)=x,(y+z)(y+x)=2y,(z+x)(z+y)=3z,求x,y,z f(x,y,z)=(x^2+y^2)^0.5+z^1.5,求 ∂f(x,y,z)/∂y 在概率论中,如何根据f(x,y)求f(z)(Z=|X+Y|或者Z=|X-Y|) x+2y=3x+2z=4y+z 求x:y:z 已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值 已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值 设z=f(x^2,y,y/x)可导,求δz/δx,δz/δy x=y/z=z/3,x+y+z ＝12,求2x+3y+4z是多少, 若|x+3|+|y-2|+|2×z+1|=0求(x×z-y×z)(y-x+z)的值 设函数f可微,z=f(ye^x,x/(y^2)) 求z/x,z/y 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 分解因式:f(x,y,z)=x^2(y-z)+y^2(z-x)+z^2(x-y) 如果|x+y+z-6|+|2x+3y-z-12|+|2x-y-z|=0求x,y, 设z=f(x,y)满足x²+2y²+3z²+xy-z-9=0,求z对x的二阶偏导数. 高数求梯度设函数f(x,y,z)=(x-y)2+(y-z)2+(z-x)2,求gradf(x,y,z).我算对了吗 f(x,y,z)=In{[x^α+z^(1-α-β)]/y^β}+x/z+(z/x)^β,求 ∂f(x,y,z)/∂y