1.若|x-1|+|y+2|+|z-3|则(x+1)(y-2)(z+3)的值为A.48 B.-48 C.0 D.xyz 2.若ab>0,a+b>0则有A.a>0,b>0 B.a>0,b

若|x+3|+|y-2|+|2×z+1|=0求(x×z-y×z)(y-x+z)的值 (1)X+Y=15,Y+Z=-6,Z+X=7.(2)X+Y=-14,Y+Z=-7,Z+X=9.(3)X+Y=0,Y+Z=-1,Z+X=-1. 若xyz=1,求证 x^2/(y+z)+y^2/(z+x)+z^2/(x+y)≥3/2 若x:y:z=3:2:1,则x+2y-z/2x-y+z= 1.{x:y:z=3:4:5 2x+3y-5z=-142.{x-y-z=-1 3x+5y+7z=11 4x-y+2z=-13.{x+y=1 x+z=0 2x+y+2z=44.{x-y+z=-3 2x-y-z=-2 -3x+y+z=-15.{x-y+z=-3 3x+y-4z=6 2x+y-z=36.{x-2y+5z=16 2x+y-5z=7 2x-y+z=38 已知x:：y：z=3：4：5,(1)求x+y分之z的值；（2）若x+y+z=6,求x,y,z. 若x+y+z=3y=2z,则x/x+y+z=? 若x,y,z,满足3x+2y+z=5,2x+y-3z=1.y是非负数.求z的取值范围 1.（x+y-z)+(x-y+z)-(x-y-z) 2.2x-(3x-2y+3)-(5y-2) 求解一道数学题若x+y+z+3=2(根号x+根号y+1+根号z-1),求（x+y+z)的（y-z）次方 若x+y+z+3=2(根号x+根号y+1+根号z-1）求（x+y+z）y-z x,y,z为正数,x+y+z=3/（xyz）.1.求x+y+z最小值.2.若xyz=3,x^2+2y^2+z^2=1,求x的范围 ..1.x+y+z=26,2.4y+3z=7,y-z=1,3x+2z=17,x+2y-z=18 9x-7y=173.x-7y+3z=17 4.2x+4y+3z=95x-6y-z=24 3x-2y+5z=113x+7y-2z=1 5x-6y+7z=131.x+y+z=26,y-z=1x+2y-z=18 2.4y+3z=7,3x+2z=11,9x-7y=17 3.x-7y+3z=17 5x-6y-z=24 3x+7y-2z=14.2x+4y+3z=93x-2y+5z=11 5x-6y+7z=13 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 1.若3x-2y+z=2;3x+2y+5z=4,求x+22.若x-3y+z=0;3x-3y-4z=0,求x:y:z 若|x-3|+|y+2|+|2z+1|=0,求(xy-yz)(y-x+z)