Correct option (C), (D)
Explanation :
Let A = (t12, 2t1) and B = (t22, 2t2)(t1 ≠ t2)Therefore, the slope of AB is
2/t1 + t2 ...(1)
Now, C is the centre of the circle described on AB as diameter (see Fig), which is given by
Therefore, the radius is
|t1 + t2| = r (∴ the circle touches the axis)
So, the slope of AB r = ± 2/r .