$\"\"$

\

The definite integral is $\"\"$ .

\

Rewrite the integral.

\

$\"\"$

\

Trigonometric identity : $\"\"$ .

\

$\"\"$

\

Integral formula: $\"\"$ .

\

Integral formula: $\"\"$ .

\

$\"\"$

\

$\"\"$ .

\

$\"\"$

\

$\"\"$ .