(a)
\The function is
.
Find the critical numbers by applying derivative.
\
Apply derivative on each side with respect to
.

Equate the derivative to
.

The function has a discontinuity at
.
Therefore critical number is
.
(b)
\The function has a discontinuity at
.
So we need consider the discontinuity while setting the test intervals.
\Consider the test intervals to find the interval of increasing and decreasing.
\Test intervals are
,
and
.
| Test interval | \Test value | \Sign of ![]() | \
Conclusion | \
![]() | \
![]() | \
\
| \
Decreasing | \
| \
![]() | \
\
| \
Increasing | \
![]() | \
![]() | \
\
| \
Decreasing | \
The function
is increasing on the intervals
and
.
The function
is decreasing on the intervals
and
.
(c)
\Use first derivative test to identify all relative extrema.
\
changes from positive to negative at
. [From (b) ]
Therefore according to first derivative test , the function has maximum at
.
The function
has a relative maximum at
.
Find
.

So the function
has relative maximum at
.
(d)
\Graph the function is
.

Now observe the graph :
\Critical number is
.
The function has a discontinuity at
and
.
The function
is increasing on the intervals
and
.
The function
is decreasing on the intervals
and
.
The function
has relative maximum at
.
(a)
\Critical number is
.
\
The function has a discontinuity at
and
.
(b)
\The function
is increasing on the intervals
and
.
The function
is decreasing on the intervals
and
.
(c)
\The function
has relative maximum at
.
(d)
\Graph of the function is
.
