\
The integral is .
The function is and the interval is
.
Find the absolute minimum and maximum values in the interval .
.
Differentiate on each side with respect to .
.
Find the critical number by equating to zero.
General solution of cosine function is .
For then
is not in the interval
, hence it is not considered.
.
Find the value of the function at the critical number .
\
Find the value of the function at the end points at .
Substitute in the function.
Substitute in the function.
Therefore, absolute minimum of the function in the is
.
Absolute minimum of the function in the is
.
.
Comparison property of integrals:
\If for
, then
.
Here and
.
By comparison property of integrals :
\\
.