determine all vectors in R2 that are orthogonal to u 4 2Sol
determine all vectors in R^2 that are orthogonal to u = (4, 2).
Solution
Let the vector orthogonal to u be v.
v = (v1,v2)
u.v = 0 (since, dot product of orthogonal vector is zero)
4v1 + 2v2 = 0
2v1 = -v2
Therefore, all vectors which are orthogonal to u is (k,-2k) where k belongs to R.

