Let D1 = ∣∣ ∣∣aba+bcdc+daba−b∣∣ ∣∣ and D2= ∣∣ ∣∣aca+cbdb+daca+b+c∣∣ ∣∣ then the value of D1D2 where b≠0 and ad≠bc, is
A line meets the co-ordinate axes in A & B, a circle is circumscribed about the triangle OAB. If d1 and d2 are the distances of the tangent to the circle at the origin O from the points A and B respectively the diameter of the circle is: