132k views
2 votes
Find two unit vectors orthogonal to both given vectors. i j k, 9i k

1 Answer

2 votes

Final answer:

To find two unit vectors orthogonal to î and 9î + â, we perform a cross product yielding -à and the negation of this result, which is à. Both vectors are along the y-axis and orthogonal to the original vectors.

Step-by-step explanation:

To find two unit vectors that are orthogonal to both î and 9î + â, we can take their cross-product. According to the properties of cross products, the result will be orthogonal to both vectors. Since our given vectors already lie in the xz-plane, the resulting cross-product will be along the y-axis, due to the cyclic order of the unit vectors in three-dimensional space.

The original vectors can be written as (1, 0, 0) and (9, 0, 1) respectively. The cross-product of these vectors is obtained by computing the determinant of the following matrix:

| î à â |
| 1 0 0 |
| 9 0 1 |
Which results in:î(0*1 - 0*9) - à(1*1 - 0*9) + â(1*0 - 0*9) = 0î - 1à + 0â = -à
The resulting vector is -1à, which is already a unit vector and is orthogonal to both original vectors. The other orthogonal unit vector will be just the negation of this result, which is 1à, as negating a vector does not change its length but makes it point in the opposite direction.
User Pedro Gordo
by
7.5k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.