3.4 Concavity and the second derivative test.notebook

3.4 Concavity and the second derivative test.notebook
October 01, 2014
Section: 3.4 Concavity and the second derivative test
Objective:
• Determine intervals on which a function is concave upward or concave downward
• Find any points of inflection of the graph of a function
• Apply the second derivative test to find relative extrema of a function
Homework: Pg 194 # 3­54 x 3 55, 59
Copy into notes. or page of things to memorize
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3.4 Concavity and the second derivative test.notebook
October 01, 2014
Concavity: Let f be differentiable on an open interval I. The graph f is concave upward on I if f ' is increasing on the interval and concave downward on I if f ' is decreasing on the interval.
Second derivative test (informal):
• If f " is positive on an interval, then the function is concave upward.
• If f " is negative on an interval, then the function is concave downward.
Point of inflection (Informal): When a graph changes concavity there is a point of inflection.
• If (c,f(c)) is a point of inflection on the graph of f , then either f "(c) = 0 or DNE at x = c
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3.4 Concavity and the second derivative test.notebook
October 01, 2014
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3.4 Concavity and the second derivative test.notebook
October 01, 2014
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3.4 Concavity and the second derivative test.notebook
October 01, 2014
f " is positive when f ' is increasing => concave up
f " is negative when f ' is decreasing => concave down
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3.4 Concavity and the second derivative test.notebook
October 01, 2014
is increasing
If
is positive
If is negative
If is = 0 or DNE
If is positive
If
is negative
if is = 0 or DNE Possible point of inflection
If
is increasing
Is positive
If is decreasing
Is negative
is decreasing
Critical number (possible min or max
Concave up
Concave down
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3.4 Concavity and the second derivative test.notebook
October 01, 2014
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3.4 Concavity and the second derivative test.notebook
October 01, 2014
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3.4 Concavity and the second derivative test.notebook
October 01, 2014
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3.4 Concavity and the second derivative test.notebook
October 01, 2014
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3.4 Concavity and the second derivative test.notebook
October 01, 2014
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3.4 Concavity and the second derivative test.notebook
October 01, 2014
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3.4 Concavity and the second derivative test.notebook
October 01, 2014
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