Find the projection of u onto v if u = (1,5), v= (-2,-3)

"Find the projection of u onto v if u = (1,5), v= (-2,-3)"

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Find the projection of u onto v if  u = (1,5), v= (-2,-3)

We have......

proj_v u  =   [  u (dot) v ] * v / ll v ll²

u (dot ) v =  1*-2 + -3 * 5 =  -2 + - 15   =  -17

ll v ll  =  √ [ 2^2 + 3^2 ] = √ 13     so  ll v ll² = 13

So 

proj_v u  =   [ -17] * < -2, -3 > / 13  =     <  34/13 , 51/13  >