How do you find two unit vectors which are orthogonal to the vector 3i-j+2k and parallel to the yz plane?

1 Answer
Jul 21, 2016

General solution is (+-(2+c, 3 c, -3))/|((2+c, 3 c, -3))|
Particular solutions for + sign, and c =0 and 1, are
1/sqrt 13(2, 0, -3) and 1/sqrt 3(1, 1, -1), respectively.

Explanation:

A vector parallel to yz-plane is p=j+ck=(0, 1, c), with c at your

choice..

The other given vector is q=3 i-j+2 k=(3, -1, 2)

Now, r=+-(p X q)=+-((0, 1, c) X (3, -1, 2)

=+-(2+c, 3 c, -3) is

orthogonal to both p and q..

Such orthogonal unit vectors, for + sign, and c =0 and 1, are

1/sqrt 13(2, 0, -3) and 1/sqrt 3(1, 1, -1), respectively.

The general solution is

(+-(2+c, 3 c, -3))/|((2+c, 3 c, -3))|, where c i a parameter.