Where to place a thin lens to couple a ray into a fiber

STINGERX
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Homework Statement


i need to couple a ray (point source 15 deg) into a fiber with a small core diameter, the fiber located 8cm from the source.
the focal distance of the lens is 1.5cm
i need to choose 2 possible locations

Homework Equations

The Attempt at a Solution


first suggestion:
i placed the lense in the focal distance from the fiber

second suggestion:
i placed the lense in the middle between the source and the fiber (in this location the transverse magnification equal to -1 meaning that the point source will not get bigger,am i correct?
 
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Neither of those locations seems correct to me. The central location is an especially poor choice.

How are the focal length, the object distance, and the image distance all related?
 
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