\
The function is .
(A)
\Domain :
\The function is .
Function inside the logarithm value should be greater than zero.
\ is always greater than zero.
All possible values of is the domain of the function.
Therefore the domain of the function is the set of all real numbers.
The domain of the function is
.
\
(B)
\Intercepts :
\To find the -intercepts, substitute
in the function.
The -intercept is
.
To find the -intercepts, substitute
in the function.
The -intercept is
.
\
(C)
\Symmetry :
\Substitute in the function.
Here , hence the function is a even function.
Therefore the function is symmetric with respect to
axis.
\
(D)
\Asymptotes :
\There is no vertical asymptotes, since the function is continuous at all real numbers.
\Horizontal asymptote :
\No logarithmic function has horizontal asymptotes.
\There is no horizontal asymptote.
\\
(E)
\Intervals of increase or decrease :
\The function is .
Differentiate on each side with respect to
.
Find the critical points.
\Critical points exist when .
Equate to zero.
The critical points are .
The test intervals are and
.
Interval | \Test Value | \Sign of ![]() | \
Conclusion | \
![]() | \
![]() | \
\
| \
Decreasing | \
![]() | \
![]() | \
\
| \
Increasing | \
The function is decreasing on the intervals .
The function is increasing on the interval .
\
(F)
\Local Maximum and Minimum values :
\The function has a local minimum at
, because
changes its sign from negative to positive.
Substitute in
.
Local minimum is .
\
(G)
\Concavity and point of inflection :
\.
Differentiate on each side with respect to
.
Find the inflection points.
\Equate to zero.
Substitute in
.
Inflection point is .
Substitute in
.
Inflection point is .
The test intervals are
and
.
\
Interval \ | \
Test Value | \Sign of ![]() | \
Concavity | \
![]() | \
![]() | \
\
| \
Concave Down | \
![]() | \
![]() | \
\
| \
\
\ Concave Up | \
![]() | \
![]() | \
\
| \
Concave Down | \
The graph is concave up in the interval .
The graph is concave down in the interval and
.
The inflection points are and
.
(H)
\Graph :
\Graph of the function :
(A) Domain of the function is .
(B) -intercept is
. and
-intercept is
.
(C) Symmetric on axis.
(D) No asymptotes.
\(E)
\The function is decreasing on the intervals .
The function is increasing on the interval .
(F)
\Local minimum is .
(G)
\The graph is concave up in the interval .
The graph is concave down in the interval and
.
The inflection points are and
.
(H) Graph of the function is .
.