已知x、y满足x2+y2=4,则z=3x-4y+5的取值范围是( )
已知x、y满足x2+y2=4,则z=3x-4y+5的取值范围是( )
已知实数x,y满足x2+y2=4,求x+y的取值范围
已知实数x.y满足x2+y2=4.则3x+4y的取值范围是
已知实数xy满足x2+y2-4x+3=0则(x+y-3)/(x-y+1)的取值范围是
已知实数x,y满足x2+ y2=6x,则z=x2+y2+2x的取值范围
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x,y满足x2/9+y2/4=1,则xy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?
已知函数x,y满足x2+y2=2x,则x2+y2的取值范围
已知实数x,y满足x2+y2+4x+3=0,求(y-2)/(x-1)的取值范围.
已知实数x,y满足方程x2+y2-4x+1=0,则yx+1的取值范围是( )
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