$\"\"$

The two vectors $\"\"$ and $\"\"$ are orthogonal unit vectors.

If $\"\"$ and $\"\"$ are orthogonal, then $\"\"$ .

If $\"\"$ and $\"\"$ are unit vectors then $\"\"$ and $\"\"$ .

Apply formula: $\"\"$ .

Substitute $\"\"$ and $\"\"$ .

$\"\"$

$\"\"$ .

If $\"\"$ then $\"\"$ is called as unit vector.

$\"\"$

$\"\"$ is called as unit vector..