How we find unit vector in specefic direction ?

Unit vectors have length 1. To make any vector a unit vector, divide the vector by its length.

Every nonzero vector has a corresponding unit vector, which has the same direction as that vector but a magnitude of 1. To find the unit vector u of the vector: v= <x,y>, you divide that vector by it's magnitude as u= v/ |v| (v over vertical bar v vertical bar). Best to google on Dummies for detailed steps. 

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