$\"\"$

\

The expression is $\"\"$ .

\

Simplify the expression.

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

Pythagorean identity : $\"\"$ .

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

Cancel common terms.

\

$\"\"$

\

Reciprocal identity : $\"\"$ .

\

$\"\"$ .

\

$\"\"$

\

$\"\"$ .