题干

在平面直角坐标系xOy中,已知椭圆C:
x
2
a
2
+
y
2
b
2
=1a>b>0的离心率e=
2
3
,且椭圆C上的点到点Q(0,2)的距离的最大值为3.
求椭圆C的方程
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答案(点此获取答案解析)

解:由e=
2
3
得a2=3b2,椭圆方程为x2+3y2=3b2

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One day during elementary school, I was terribly ill. My mother came.     "Your mom only has one eye?!" asked some of my classmates. I was so  2 .     I wished my mother would just disappear from this world. "If you make me teased(嘲笑),why don't you just die?" I shouted at her, taking no notice of the sad look on her face. My mother just handed me some  3and left without saying    4   .     At that time, I felt  5  to say what I always wanted to say, and I didn't think I had hurt her feelings very much. That night I saw my mom      6  in her room, so quietly, as if she was afraid that she might   7  me. Even so, I hated her tears from one eye. I made a   8  : I must study hard and leave my mother.     Years later my dream came true. I was quite successful and lived  9 . I never thought of going back to see my "ugly" mother  10 one day I got a letter, which said, "My son... I'm sorry I only have one eye. When you were little, you got into a(n)  11   and lost your eye. As a mom, I couldn't   12  watching you live with only one eye.  13   I gave you mine. I was never  14   with you and I never regretted(后悔) what I did because I    15   you…"     I cried out aloud. Only then did I realize how beautiful my mother was!