已知z2=x2+y2,化简(x+y+z)(x-y+z)(-x+y+z)(x+y-z).
已知x,y,z满足x/(y+z)+y/(z+x)+z/(x+y)=1,求代数式x2/(y+z)+y2/(x+z)+z2/
已知实数x,y,z满足x/(y+z)+y/(z+x)+z/(x+y)=1,求x2/(y+z)+y2/(z+x)+z2/(
不等式选讲设x,y,z为正数,证明:2(x3+y3+z3)≥x2(y+z)+y2(x+z)+z2(x+y).
若正数x,y,z满足x+y+z=3,x2+y2+z2=9/2,则z的最大值为多少?(详解)
已知x2+y2+z2-2x+4y-6z+14=0,则x+y+z=______.
①(x+y+z)(-x+y+z)(x-y+z)(x+y-z)
(选做题)已知x2+3y2+4z2=2,求证:|x+3y+4z|≤4.
若实数x,y,z满足x+2y+3z=a(a为常数),则x2+y2+z2的最小值为______.
x分之y+z=y分之z+x=z分之x+y(x+y+z不等于0),求x+y+z分之x+y-z
已知整数 x,y ,z ,满足 x≤y <z ,且 那么x2+y2+z2的值等于( )
1.已知x2+y2+z2-2x+4y-6z+14=0,求x+y+z的值.
已知x2+4y2+z2-2x+4y-6z+11=0 求x+y+z的值