设A(x1,y1)B(x2,y2)是双曲线上两点中点P(x,y)所以x1^2/a^2--y1^2/b^2=1x2^2/a2--y2^2/b2=1上面两式做差整理得(y1-y2)/(x1-x2)=b^2(x1+x2)/a^2(y1+y2)因为(y1-y2)/(x1-x2)=mx1+x2=2x,y1+y2=2y所以m=b^2x/a^2yy=b^2/a^...