x(1/y+1/z)+y(1/x+1/z)+z(1/x+1/y)+3=0,且1/x+1/y+1/z不等于0,求x+y+z的值

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)=? 1、y-x/x²-y²2、(x-y)(y-z)(z-x)/(z-y)(y-x)(x-z) X>Y>Z,试确定1/(X-Y)+1/(Y-Z)+1/(Z-X)的符号 {x+y-z=11 y+z-x=5 z+x-y=1 {x+y-z=11,x-y-z=-5,x-y+z=1 分解因式：（1):x(x-y)+y(y-X) 多项式(x+y-z)(x-y+z)-(y+z-X)(Z-x-y)的公因式是多少? 若1/X 1/y 1/z 成等差数列,求证:(Y-Z-X)/X (Z+X-Y)/Y (X+Y-Z)/z也成等差数列越快越好 X/Y+Z=Y/X+Z+1=Z/X+Y-1=X+Y+Z,求x+y+z等于多少 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 x+y+z=6 x+2y+3z=14 y+1=z 已知实数X.Y.Z满足(Y+Z)分之X+(Z+X)分之Y+(X+Y)分之Z=1,则(Y+Z)分之X平方+(Z+X)分之Y平方+(X+Y)分之Z平方的值为（ ） 有谁能帮俺解释一下++x||++y&&++z是什么意思啊?main(){int x,y,z (x,y,z);x=y=z=1; ++x||++y&&++z; printf(x=%d,y=%d,z=%d ,x,y,z) } 若|x+3|+|y-2|+|2×z+1|=0求(x×z-y×z)(y-x+z)的值 f(x,y,z)=In{[x^α+z^(1-α-β)]/y^β}+x/z+(z/x)^β,求 ∂f(x,y,z)/∂y matlab解对数方程组[x,y,z]=solve('0.29744*x/(3+0.1*x+y+z)=(log10((3+x+y+z)/(3+0.1*x+y+z)))^2','0.79*x/(3+0.1*y+z)=(log10((3+x+y+z)/(3+0.1*x+y+z)*(3+y+z)/(3+0.1*y+z)))^2','1.25*x/(3+0.1*z)=(log10((3+x+y+z)/(3+0.1*x+y+z)*(3+y+z)/(3+0.*1y+z)*(3+z)/ (x+y+z)÷10=x+1.1 y+x=z-80+y-1 z-y=8x+y+8 x+z÷y=? 计算x/y+x=y/x+z+1=z/x+y-1的值