What is the projection of #<5,6,1 ># onto #<8,-5,1 >#?

1 Answer
Feb 15, 2016

#vec C= <88/90 ,-55/90,11/90>#

Explanation:

#vec A= < a,b,c >#
#vec B= < d,e,f >#
#"Projection of A onto B is given as :"#
#vec C= (vec A .vec B)/(||vec B||^2)vec B#
#vec A* vec B=a.d+b.e+c.f=40-30+1=11#
#"magnitude of "vec B=sqrt (64+25+1)=sqrt 90#
#vec C=11/90<8,-5,1>#
#vec C= <88/90 ,-55/90,11/90>#