Analytical Applications of Differentiation
The Second Derivative Test allows us to determine:
The x-coordinate of inflection points.
The concavity and nature of the extrema.
The absolute extrema of a function.
The slope of the tangent line at critical points.
Why is it necessary to know the signs of the first and second derivative when using the second derivative test for extrema?
Knowing only the second derivative suffices for applying the second derivative test.
The sign of the first derivative shows a function is increasing or decreasing near a critical point, while the second sign indicates concavity or convexity at that point.
The first derivative sign shows the presence of an inflection point; the second sign determines if the inflection is a maximum or minimum.
The sign of the first derivative is the main indicator for potential extremal points regardless of the second.
Given a continuous function with a critical point at , what does imply about the behavior of at that point?
The function has a local minimum at .
The function has a local maximum at .
The concavity of the function cannot be determined at .
The function has an inflection point at .
If the second derivative is negative at a critical point, then the critical point corresponds to:
A point of discontinuity.
A relative minimum.
An inflection point.
A relative maximum.
If, for a differentiable function , we find that and , what can we conclude about point on its graph?
No conclusion can be drawn because more information is needed.
It is an inflection point where concavity changes.
It is a local minimum.
It is a local maximum.
What happens when you apply the Second Derivative Test to a critical point and find out that ?
There must be an error in calculation as this result isn't possible for extrema tests.
It confirms you have found either an extremum or an inflection point but does not indicate which one it could be.
The test is inconclusive; use another method to determine extrema or points of inflection.
You have found neither extremum nor inflection; move on without further analysis.
If the second derivative is positive for all x-values in a given interval, then:
The function is increasing in that interval.
The Second Derivative Test cannot be applied.
The function is decreasing in that interval.
The function has a relative minimum in that interval.

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The Second Derivative Test is applicable when the function is:
Twice differentiable.
Concave upward.
Increasing.
Continuous.
Which statement below accurately describes how you would use derivatives to find points where a function could have extrema?
Find values where only second-derivative test fails; use first-derivative test instead.
Find values where or where does not exist; then test with .
Only find values where both and are equal to zero simultaneously.
Find values where only ; ignore .
When the second derivative is positive, the graph of the function is:
Constant.
Increasing.
Concave upward.
Concave downward.