解x+2y+z=8,2x-y-z=-3,3x+y-2z=-1和x+2y+3z=4,y+z=1,3x+2z=3

试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y) 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/x+y=y+z/2(y-z)=z+x/3(z-x),求证8x+9y+5z=0THX.. 急 x,y,z均为正整数,x>=y,y>=z,z>=8 x+3y-z=急x,y,z均为正整数,x>=y,y>=z,z>=8x+3y-z=132,请问1.x+y+z有最小值782.x+y+z有最大值1343.洽有一组解(x,y,z)使得x+y+z有最大值4.x+3y有最小值1405.x+2y有最大值130 X/10=Y/8=Z/9,则X+Y+Z/2Y-3Z 解方程 x+y+z=10,x+3y+2z=17,y-x+3z=8 解三元一次方程：x+y-z=0,2x+y+z=7,x-3y+z=8 解方程组x+y-z=0,2x+y+z=7,x-3y+z=8 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)/ (4x-2y-z)-{5x-[8y-2z-(x-2y)]-x-(3y-10z)}=? 解三元一次方程组1、x+y-z=4 2x-y+z=5 x-3y+z=-2 2、y+2z=-2 3x+y-4z=1 2x-y+2z=8 3、x-2y+z=-1 x+y+z=2x+2y+3z=-1 证明 ：x/(y+z)+y/(z+x)+z/(x+y)>=3/2其中 x,y,z>0 解x+2y+z=8,2x-y-z=-3,3x+y-2z=-1和x+2y+3z=4,y+z=1,3x+2z=3 3x-y+z=4,2z+3y-z=12,x+y+z=6的解 {x+y+z=1;x+3y+7z=-1;z+5y+8z=-2 解y+2z=-2;3x+y-4z=1;2x-y+2z=8 x/2=y/3=z/5 x+3y-z/x-3y+z x+2y=3x+2z=4y+z 求x:y:z