题目

如图，在平面直角坐标系xOy中，椭圆的离心率为，过椭圆右焦点作两条互相垂直的弦与．当直线斜率为0时，．（1）求椭圆的方程；（2）求的取值范围． 答案：【答案】（1），（2）．【解析】试题分析：（1）求椭圆标准方程，只需两个独立条件. 一个是,另一个是点在椭圆上即，所以．所以椭圆的方程为．（2）研究直线与椭圆位置关系，关键确定参数，一般取直线的斜率，① 当两条弦中一条斜率为0时，另一条弦的斜率不存在，由题意知，② 当两弦斜率均存听两遍。根据你所听到的短文内容，从A、B、C三个选项中选出正确答案。1. Mike is from ______.A. JapanB. CanadaC. England 2. The teachers and the students in Beijing No. 1 Middle School are ______.   A. interestingB. friendlyC. lazy3. Mike has ______ classes a day.  A. fiveB. two C. seven4. After school, Mike often ______for half an hour.  A. does his homeworkB. plays soccer ball C. watches TV5. Mike's mother likes to be a policewoman because it's a _____ job. A. fun and dangerousB. fun and excitingC. relaxing and fun