(2/2),且OM垂直ON(O为坐标原点),求M的值.

问题描述:

(2/2),且OM垂直ON(O为坐标原点),求M的值.

设M(x1,y1)N(x2,y2)OM垂直ON,
(y1/x1)*(y2/x2)=-1
4(2-y1)(2-y2)=-y1y2
16-8(y1+y2)+5y1y2=0
x+2y-4=0代入(x-1)^2+(y-2)^2=5-m
5y^2-16y+(8+m)=0
y1+y2=16/5
y1*y2=(8+m)/5
m=8/5