实数xy满足x2—2x—4y=5,记t=x-2y,则t的取值范围
实数xy满足x2—2x—4y=5,记t=x-2y,则t的取值范围
实数x,y满足x²-2x-4y=5,记t=x-2y,则t的取值范围为
设实数xy满足x2 +2y2=6,则x+y的取值范围
实数x,y满足x²-2x-4y=6,记t=x-2y,则t的取值范围是
实数x,y满足x平方-2x-4y=6,记t=x-2y,则t的取值范围
实数x,y满足x²-2x-4y=6,若t=x-2y,则t的取值范围
已知正实数x,y满足2x+2y+xy=5 则xy的取值范围是什么?
实数x、y满足x2+xy+y2=2,记u=x2-xy+y2,则u的取值范围是
设实数x,y满足x2+y2=1则 xy的取值范围是?
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______.
实数x、y满足x^2;+xy+y^2;=2,记u=x^;-xy+y^2;,则u的取值范围是yiz
(2008•杭州一模)设实数x,y满足x2+2xy-1=0,则x+y的取值范围是______.