设A(x1,y1),B(x2,y2),联立败州x^2/a^2+y^2/b^2=1与y=x-1,得(a^2+b^2)x^2-2a^2x+a^2-a^2b^2=0,x1+x2=2a^2/(a^2+b^2),x1x2=(a^2-a^2b^2)/(a^2+b^2),由OA垂直OB,派枯好即x1x2+y1y2=0,即x1x2+(x1-1)(x2-1)=0代入尘铅算出即可
列方程求解,不会就多看点书吧