The trigonometric equation is
.
To solve
on a calculator, first set the mode to radians.
If
.

.
Round to two decimal values.
\
.
The solution
is lies in the interval
.
One solution of the equation is
in
is
.
The general solution of
is
, where
is an integer.
.
Substitute
in the above expression.
.
Round to two decimal values.
\
.
The solution set for
is
.
The solution set for
is
.