If the bisector of the angles between the pairs of lines given by the equation ax2+2hxy+by2=0 and ax2+2hxy+by2+λ(x2+y2)=0 be coincident, then λ =
Bisectors of ax2+2hxy+by2=0 arex2−y2a−b=xyh ......(i)and ofax2+2hxy+by2+λ(x2+y2)=0i.e., (a+λ)x2+2hxy+(b+λ)y2=0 arex2−y2(a+λ)−(b+λ)=xyh⇒ x2−y2a−b=xyh........(ii)