Question

如图,圆x^2+y^2=9与x轴交于点A1、A2,MN是垂直于x轴的弦,求直线A1M与A2你的交点P的轨迹方程

Answer 1

M(x1,y1),N(x1,-y1),P(x,y) A1(-3,0),A2(3,0)

则 x12+y12=9

且 y/(x+3)=y1/(x1+3),y/(x-3)=-y1/(x1-3)

相乘得：y2/(x2-9）=-y12/(x12-9) =1 y2=x2-9 x2- y2=9