$\"\"$

Let the vectors are $\"\"$ and $\"\"$ .

The vectors $\"\"$ and $\"\"$ are perpendecular(orthogonal) If $\"\"$ .

The dot product of the vectors $\"\"$ and $\"\"$ is defined as $\"\"$ .

$\"\"$

Since the dot product is equals to zero, the vectors $\"\"$ and $\"\"$ are perpendecular to each other.

$\"\"$

The vectors $\"\"$ and $\"\"$ are perpendecular to each other.