\
(a)
\Thu function is
,
.
Differentiate
on each side with respect to
.

Find the critical points.
\Thus, the critical points exist when
.
Equate
to zero:

The general solution of cosine function is
, where 
The solution for
is
,
.
and
and
.
The critical points are
and
and
.
The test intervals are
and
.
| Interval | \Test Value | \Sign of ![]() | \
Conclusion | \
![]() | \
![]() | \
\
| \
Increasing | \
![]() | \
![]() | \
\
| \
Increasing | \
The function is increasing over the interval
.
\
(b)
\Find the local maximum and local minimum.
\Since the function is increasing, therefore it has neither local maximum nor minimum.
\\
(c)
\
.
Differentiate
on each side with respect to
.

Find the inflection points.
\Equate
to zero.

The general solution of sine function is
, where
.
The solution for
is
,
.
,
and
.
The inflection points are at
,
and
.
Substitute
in 

.

Substitute
in 
.

Substitute
in
.

The test intervals are
,
,
and
.
| \
Interval \ | \
Test Value | \Sign of ![]() | \
Concavity | \
![]() | \
![]() | \
\
| \
Up | \
![]() | \
![]() | \
\
| \
\
Down \ | \
![]() | \
![]() | \
\
| \
\
Up \ | \
![]() | \
![]() | \
\
| \
Down | \
The graph is concave up on the intervals
and
.
The graph is concave down on the intervals
and
.
The inflection points are
,
and
.
\
(d)
\Graph :
\Graph the function
:
.gif\")
\
(a)
\The function is increasing over the interval
.
(b)
\There is neither local maximum nor local minimum.
\(c)
\Concave up in the intervals
and
.
Concave down in the intervals
and
.
Inflection points are
,
,
,
and
.
(d)
\Graph of the function
is
.