已知实数x,y满足x2+ y2=6x,则z=x2+y2+2x的取值范围
已知实数x,y满足x2+ y2=6x,则z=x2+y2+2x的取值范围
设实数xy满足x2 +2y2=6,则x+y的取值范围
已知实数x,y满足x2+y2=4,求x+y的取值范围
已知函数x,y满足x2+y2=2x,则x2+y2的取值范围
已知a>0,实数x,y,z满足x+y+z=a,x2+y2+z2=a2/2,求x的取值范围
已知实数x,y,z满足以下条件,求x的取值范围.x+y+z=a,x2+y2+z2=1/2 a2
已知实数x,y满足x2+y2=2x,则x2y2的取值范围是______.
已知实数x,y满足x2+y2-4x+1=0,求2x+y的取值范围?
已知x、y是实数且满足x2+xy+y2-2=0,设M=x2-xy+y2,则M的取值范围是______.
若实数x,y,z满足x+2y+3z=a( a为常数 ),则x2 + y2 + z2的取值范围是
已知实数x.y满足(x2+y2)(x2+y2-1)=2,求x2+y2的值
设实数x,y满足x2+y2=1则 xy的取值范围是?