There are an infinite number of vectors that will be orthogonal to <1,3,10> and once  you have a vector that meets this condition, then you can scale it to a length of 3.

There are an infinite number of vectors that will be orthogonal to <1,3,10> and once you have a vector that meets this condition, then you can scale it to a length of 3.
Method #1: Consider the vector <x,y,z> that is perpendicular to our given vector. Thus
now pick any value for y and z and then use those values to compute x.
Method #2: Pick any non­zero vector that is not parallel to the vector <1, 3,10> say <1,0,0>. Then the cross product of these vectors will be perpendicular to both <1,3,10> and <1,0,0>.
now scale this vector to a length of 3.
Title: Apr 20­2:15 PM (1 of 1)