The function is
.
Find the critical numbers by applying derivative.
\
Equate it to zero.
\
Therefore the critical number is
.
The critical point is
.
Test intervals are
and
.
| Test intervals | \ \
Test value \ | \
\
Sign of | \
Conclusion | \
![]() | \
![]() | \
\
| \
Decreasing | \
![]() | \
![]() | \
\
| \
Increasing | \
The function
is decreasing on the interval
.
The function
is increasing on the interval
.
The function
is decreasing on the intervals
.
The function
is increasing on the interval
.