Ray Optics and Optical Instruments Part 1

Object is at 2f. So image will also be at '2f'.
Image of I1 will be 1m behind mirror. i.e. ⇒I2
Now I2 will be object for lens.
∴u=−3m
f=+0.5m

1

v

⇒

1

f

+

1

u

=

1

+0.5

+

1

−3

v=35=0.6m
So total distance from mirror =2+0.6
⇒2.6m and real image