The value of the of `d_(1)` and `d_(2)` for final rays to be parallel to the principle axis are (focal lengths of the lenses are written on the lenses).

The values of d_(1) & d_(2) for final rays to be parallel to the principal axis are: (focal lengths of the lenses are written above the respective lenses in the given figure)

The values of d_(1) & d_(2) for final rays to be parallel to the principal axis are: (focal lengths of the lenses are written above the respective lenses in the given figure)

What should be the value of distance d so that final image is formed on the object itself. (Focal length of the lenses are written on the lenses.)

What should be the value of distance d so that final image is formed on the object itself. (Focal length of the lenses are written on the lenses.)

Two lenses of power 6 D and – 2 D are combined to form a single lens. The focal length of this lens will be

Two lenses of power 6 D and – 2 D are combined to form a single lens. The focal length of this lens will be