Hi IITIAN007 its a ques based on a very simple concept :Rays emerging from an object at the focus of the combination would appear to diverge from the radius of curvature of the diverging mirror.

Hence applying 1/v-1/u=1/f  for the lens

1/(2fdiv+d) -1/u=1/fcon

Since the image will b formed to the right of the diverging mirror at R=2fdiv from the mirrors pole , wrt to the lens it will b at distance R+d

=> on solving u=fcon*(2fdiv+d)/(fcon-(2fdiv+d))