数学!!在线等待!!!直线x+y=1与双曲线x^2/a^2
直线x+y=1与双曲线x^2/a^2-y^2/b^2=1,(a>0,b>0),交与MN两点,向量OM*向量ON=0,(O为坐标原点),若0
设M(x1,y1),N(x2,y2),把y=1-x代入b²x²-a²y²-a²b²=0得 (a²-b²)x²-2a²x+a²(1+b²)=0, ∴ x1+x2=2a²/(a²-b²), x1x2=a²/(a²-b²).y1y2=(1-x1)(1-x2) =1+x1x2-(x1+x2)=(a²b²-b²)/(a²-b²). ∵ 向量OM*向量ON=0, ∴ x1x2+y1y2=0,可得2a²=(2-e²)/(1-e²), ∵ 01 ∴ 1