Michael D. answered 03/14/23
PhD in Math with 20+ Years Teaching and Tutoring Experience
The (orthogonal) projection of v onto w is given by the scalar
[(v . w)/(v . w)]
multiplied by the vector w. Here the . is the vector dot product. In this case:
- v . w = 2*3 + 6*3 = 24
- w . w = 3*3 + 3*3 = 18
Thus the projection is (24/18) w = <4, 4>.
You can always check your work by computing v - (proj) and verifying that the dot product with (proj) is zero.