Find the vector projection of u onto v. Then write u as the sum of two orthogonal​ vectors, one of which is proj (Subscript v)u.

Answer 1

well, the projection of u onto v is

(u.v)/|v|

Then recall that v = |u|cosθ v/|v|
and the orthogonal component of u is |u|sinθ w/|w|
where w is orthogonal to v