$\"\"$

The trigonometric function is $\"\"$ and the quadrant is second.

The pythagorean identity is $\"\"$ .

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

$\"\"$ (Simplify)

The cosine is positive in quadrant II, so the positive root to obtain

$\"\"$ (Take root each side)

The reciprocal identity is $\"\"$ .

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

The values of $\"\"$ .