What is the meaning of doing orthogonal projection?
Every website,every teacher will tell the students that if you want to project a vector onto another vector,you can use $proj_vy=\frac{\vec y\cdot \vec v}{|\vec v|^2}\vec v$.
But none of them tell us in what situation,we will need to project a vector onto another vector,can anyone tell me in what situation,we need to project a vector onto another vector?