The two circles x2+y2−2x−3=0 and x2+y2−4x−6y−8=0 are such that

The coordinates of centres C1 and C2 of two circles are (1, 0) and (2, 3) respective. Let r1 and r2 be the radii of two circles. Then, r1=2 and r2=21.Clearly r1−r2