8、若 y,z均为质数,x=yz且 x,y,z 满足 1/x+1/y=3/z,则1998x+5y+3z=

若y,z均为质数,x=yz,且x、y、z满足1/x+1/y=3/z,则1998x+5y+3z=_____ 一道初中代数题若y,z均为质数,x=yz,x,y,z满足1/x+1/y=3/z,则1998x+5y+3z等于多少?（选项 若实数x,y,z满足x+y+z=5,xy+yz+xz=3,求z的最大值 若有理数x,y,z满足√x+√y-1+√z-2=1/2(x+y+z) 确定(x-yz)^3 时数x,y,z满足x+y+z=5,xy+yz+zx=3,求Z最大值 已知x,y,z均不为0,且满足方程组{x+y-z=0,①2x-y-5z=0.②试求(2x+y+3z)/(3x-y-z)值 已知x,y,z均不为0,且满足方程组x+y-z=0,2x-y-5z=0试求2x+y+3z/3x-y-z 已知x.y.z均为实数且满足x+y+z=4.求xy+yz+xz的最大值. 若x,y,z均为实数,且(x-1)²+|y+2|+根号（z-3）²=0则x,y,z的值分别为? 已知X Y Z为非负有理数,且满足3X+2Y+Z=5,2X+Y-3Z=1,若S=3X+Y-7Z,求S的最大值和最小值 已知x,y,z为非负有理数,且满足3x+2y+z=5,2x+y-3z=1,若S=3x+y-7z,求S的最大值和最小值 数学求最小值和最大值已知X、Y、Z为非负有理数,且满足3x+2y+z=5,2x+y-3z=1,若有S=3x+y-7z,求