What is the projection of $<3,-4,6 >$ onto $<-1,7,-3 >$ ?

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Answer 1 · 2016-03-25T13:17:00

let
$veca=<3,-4,6> =3hati-4hatj+6hatk$ and
$vecb=<-1,7,-3>= -hati+7hatj-3hatk$

The projection of $veca$ onto $vecb$ $=(veca.vecb)/|vecb|^2*vecb$
$=(-3-28-18)/((-1)^2+7^2+(-3)^2)*(-hati+7hatj-3hatk)$
$= -49/59(-hati+7hatj-3hatk)$

What is the projection of <3,-4,6 ><3,-4,6 > onto <-1,7,-3 ><-1,7,-3 >?