已知向量,满足,,与的夹角为,则的值为_______.
若椭圆的离心率为,则它的长半轴长为_______________
若,则目标函数z=x+2y的最小值为________
函数的周期是___________
.若满足2x+="5," 满足2x+2(x1)="5," 则+= ××××××.
若直线过点斜率为1,圆上恰有3个点到的距离为1, 则的值为××××××.