A result in control theory. Define
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Then in order for a control 
and a trajectory 
to be optimal, it is necessary
that there exist nonzero absolutely continuous vector
function 
corresponding to the functions 
and 
such that
1. The function 
attains its maximum at the point 
almost everywhere in the interval 
,
 |
2. At the terminal time 
, the relations 
and 
are satisfied.
