1)联立y＝ax+1 ;3x^2-y^2=1 ===>(3-a^2)x^2-2ax-2=0
因为直线与双曲线有两个交点所以△=4a^2+8(3-a^2)>0
解得-√6y＝2x+1
x1+x2=-4 ;x1x1=2 ;y1+y2=-6 ;y1y2=1
|AB|=√[(x1-x2)^2+(y1-y2)^2]=4√10