问题 填空题
已知点A(1,0),B(2,0).若动点M满足
AB
BM
+
2
|
AM
|=0,则点M的轨迹方程为______.
答案

设M的坐标为(x,y),可得

AM
=(x-1,y),
AB
=(1,0),
BM
=(x-2,y)

AB
BM
=1×(x-2)+0×y=x-2,
|AM|
=
(x-1)2+y2

∵动点M满足

AB
BM
+
2
|
AM
|=0,

∴(x-2)+

2
(x-1)2+y2
=0

移项,平方得(x-2)2=2[(x-1)2+y2]

整理,得x2+2y2=2,

所以点M的轨迹方程为:

x2
2
+y2=1.

故答案为:

x2
2
+y2=1

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