设实数x,y满足x2+y2=1则 xy的取值范围是?设实数x,y满足x2+y2=1则 xy的取值范围是________.

已知实数x,y满足x2+xy+y2=3,则x2-xy+y2的最小值 设实数x,y满足x2+y2=1则 xy的取值范围是?设实数x,y满足x2+y2=1则 xy的取值范围是________. 若实数x,y满足x2+y2+xy=1,则x+y的最大值是 若实数x,y满足x2+y2+xy=1,则x+y的最大值是 设实数x,y满足x2-xy+y2=1,求x2-y2的最大值和最小值,x2表示x的平方 设实数x,y,z满足x2+y2+z2-xy-yz-zx=27,则|y-z|的最大值为? 若实数XY满足X2+Y2=1,则X-2Y的最大值为 设正实数x,y满足x2-xy+y2=1,求x2-y2的最大值和最小值ygq23266836 大哥 你搞错了 实数x,y满足x2+y2=4,则x+y-xy的最大值无 若实数x,y满足x2+y2+x2y2-4xy+1=0,则(x+y)2的值为 实数xy满足x2+y2+2x-4y+1=0,则x2+y2-2x+1的最小值为 实数xy满足x2+y2+2x-4y+1=0,则（根号下x2+y2-2x+1）的最大值为 已知实数xy满足x2+y2=4.则y+3/x+1的取值范围为 已知实数xy满足x2+y2=4.则y+3/x+1的取值范围为 已知实数x、y满足X2+y2-xy+2x-y+1=0,试求x、y的值 已知实数x,y满足(x2)+(y2)-xy+2x-y+1=0,求x,y的值 已知实数x、y满足X2+y2-xy+2x-y+1=0,试求x、y的值 设x,y是实数,且 x2+xy+y2=3.那么,x2-xy+y2的取值范围是?