The function is , where
is a positive constant.
Graph :
\Graph the function :
The function is .
Differentiate on each side with respect to .
Find the critical points.
\The critical points exist when .
Equate to zero.
and
.
The critical points are and
.
The test intervals are ,
and
.
Interval | \Test Value | \Sign of ![]() | \
Conclusion | \
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\
| \
Increasing | \
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\
| \
Decreasing | \
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\
| \
Increasing | \
The function is increasing on the intervals and
.
The function is decreasing on the interval .
Find the local maximum and local minimum.
\The function has a local maximum at , because
changes its sign from positive to negative.
Substitute in the function.
Local maximum is .
The function has a local minimum at , because
changes its sign from negative to positive.
Substitute in the function.
Local minimum is .
.
Differentiate on each side with respect to .
Find the inflection points.
\Equate to zero.
The inflection point is .
Substitute in the function.
The test intervals are and
.
\
Interval \ | \
Test Value | \Sign of ![]() | \
Concavity | \
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\
| \
Down | \
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\
| \
\
Up \ | \
The graph is concave up on the interval .
The graph is concave down on the interval .
The inflection point is .
Observe the above tests.
\If is any positive number, the function does not change the increasing and decreasing intervals and concavity also does not change.
But local maximum and local minimum as well as inflection points varies.
\The increasing and decreasing intervals and the concavity are same.
\The local maximum and local minimum as well as inflection points differs.