Discover, as a solution (3,2)
I believe the answer is:
hit on
'discover as a solution' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for hit on that I've seen before include "Discover (something) by chance" , "Make advances to (US)" , "Discover, think of" , "try a pass?" , "Serendipitously find" .)