$\"\"$

The vectors are $\"\"$ .

The projection of u into v is $\"\"$ .

$\"\"$ (Substitute $\"\"$ )

$\"\"$ (Simplify)

$\"\"$ (Simplify) $\"\"$

The other component, $\"\"$ is $\"\"$ .

$\"\"$ (Substitute $\"\"$ )

$\"\"$ (Simplify)

The vector u write as the sum of two orthogonal vectors is $\"\"$ .

So, $\"\"$ . $\"\"$

The projection of u into v is $\"\"$ and the vector u write as the sum of two orthogonal vectors is $\"\"$ .