Задача 40543.

Image of a remote light source is projected onto the screen via lens L1 with focal length F1 = 20 cm. At a distance l = 10 cm this lens from a source placed second lens L2 with focal length F2 = 30 cm. In what direction and at what distance x need to move the screen to get it on again a sharp image of the source?

Detailed solution shorthand terms, formulas and laws used in the decision, the withdrawal of the calculation formula and the response.
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