Subject :IMO Class : Class 10
A circle with area A1 is contained in the interior of a larger circle with area A1 + A2. If the radius of the larger circle is 3 units and A1, A2, A1 + A2 are in A.P., then the radius of the smaller circle is _____.
A 
units
B 1 unit
C 2 units
D 
units