题目： 如图，直线y = mx与双曲线y = k/x相交于A、B两点，点A的坐标为(1, 3)。 (1) 求反比例函数的表达式； (2) 根据图象直接写出当mx > k/x时，x的取值范围； (3) 计算线段AB的长。 ---重难点手册 九年级数学 下册 RJ 8. 如图,直线 y=mx 与双曲线 y=k/x 相交于 A,B 两点,点 A 的坐标为(1,2). (1)求比例函数的表达式; (2)根据图象直接写出当 mx > k/x 时,x 的取值范围; (3)计算线段 AB 的长. Chart/Diagram Description: Type: Coordinate plane with graphs. Main Elements: - Coordinate Axes: Horizontal X-axis labeled 'x', vertical Y-axis labeled 'y'. Origin labeled 'O'. - Graphs: A straight line passing through the origin O, point A, and point B. A hyperbola with two branches in the first and third quadrants. - Points: Point A is shown in the first quadrant, located on both the straight line and the hyperbola. Point B is shown in the third quadrant, located on both the straight line and the hyperbola. - Labels: A, B, O, x, y are labeled on the diagram.