$\"\"$

The trigonometric identity is $\"\"$ .

Consider right hand side of the identity : $\"\"$ .

Apply quotient rule of logarthm : $\"\"$ .

$\"\"$

Apply power rule of logarthm : $\"\"$ .

$\"\"$

Apply half-angle formula : $\"italic$ .

$\"\"$

= Right hand side identity.

$\"\"$ $\"\"$ .