The trigonometric expression is
.
Rewrite the expression as
.
Find the value of the denominator:
\


Use the periodicity of the
:
.

.
Find the value of
.
Rewrite the above expression as
.

Sum and difference identity
.



Rationalize the fraction.
\


.
.
Substitute
in
.
.
Substitute
in
.
.
Rationalize the fraction.
\

.
.