Can point of inflection occur at a point where second derivative doesnot exist?












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I refered these questions
Definition of Point of Inflection
An inflection point where the second derivative doesn't exist?
What is inflection point?
I couldnt understand the necessary conditions for point of inflection.My specific doubt is
Can point of inflection occur at a point where the second derivative of a function is discontinuous?
In the image attached, the curves of the actual function, its second derivative and third derivative are given(from left to right correspondingly) Can the point x=b be an inflection point for the function.enter image description here










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  • $begingroup$
    You have answered your own question. math.stackexchange.com/questions/402459/… Yes a point where the second derivative is discontinuous at that point can be an inflection point.
    $endgroup$
    – Matthew Liu
    Feb 1 at 7:34










  • $begingroup$
    @Matthew Liu Ok.Thanks for answering.Does this mean the point x=b in the diagram can be a point of inflection for f(x) ?
    $endgroup$
    – Mohan
    Feb 1 at 7:43






  • 1




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    I think it "point of inflection" is only defined as change in sign of the second derivative and that this change of sign does not need to be continuous and go through 0. But it was ages ago I even saw this expression.
    $endgroup$
    – mathreadler
    Feb 1 at 8:06












  • $begingroup$
    @mathreadler A point of inflection is a geometric property. It's a point where the tangent line crosses the graph.
    $endgroup$
    – B. Goddard
    Feb 1 at 11:39










  • $begingroup$
    @B.Goddard Hmm if you say so. I think last time I encountered the name was in high school... Definitely did not occur particularly often at university for me.
    $endgroup$
    – mathreadler
    Feb 1 at 13:12
















1












$begingroup$


I refered these questions
Definition of Point of Inflection
An inflection point where the second derivative doesn't exist?
What is inflection point?
I couldnt understand the necessary conditions for point of inflection.My specific doubt is
Can point of inflection occur at a point where the second derivative of a function is discontinuous?
In the image attached, the curves of the actual function, its second derivative and third derivative are given(from left to right correspondingly) Can the point x=b be an inflection point for the function.enter image description here










share|cite|improve this question











$endgroup$












  • $begingroup$
    You have answered your own question. math.stackexchange.com/questions/402459/… Yes a point where the second derivative is discontinuous at that point can be an inflection point.
    $endgroup$
    – Matthew Liu
    Feb 1 at 7:34










  • $begingroup$
    @Matthew Liu Ok.Thanks for answering.Does this mean the point x=b in the diagram can be a point of inflection for f(x) ?
    $endgroup$
    – Mohan
    Feb 1 at 7:43






  • 1




    $begingroup$
    I think it "point of inflection" is only defined as change in sign of the second derivative and that this change of sign does not need to be continuous and go through 0. But it was ages ago I even saw this expression.
    $endgroup$
    – mathreadler
    Feb 1 at 8:06












  • $begingroup$
    @mathreadler A point of inflection is a geometric property. It's a point where the tangent line crosses the graph.
    $endgroup$
    – B. Goddard
    Feb 1 at 11:39










  • $begingroup$
    @B.Goddard Hmm if you say so. I think last time I encountered the name was in high school... Definitely did not occur particularly often at university for me.
    $endgroup$
    – mathreadler
    Feb 1 at 13:12














1












1








1





$begingroup$


I refered these questions
Definition of Point of Inflection
An inflection point where the second derivative doesn't exist?
What is inflection point?
I couldnt understand the necessary conditions for point of inflection.My specific doubt is
Can point of inflection occur at a point where the second derivative of a function is discontinuous?
In the image attached, the curves of the actual function, its second derivative and third derivative are given(from left to right correspondingly) Can the point x=b be an inflection point for the function.enter image description here










share|cite|improve this question











$endgroup$




I refered these questions
Definition of Point of Inflection
An inflection point where the second derivative doesn't exist?
What is inflection point?
I couldnt understand the necessary conditions for point of inflection.My specific doubt is
Can point of inflection occur at a point where the second derivative of a function is discontinuous?
In the image attached, the curves of the actual function, its second derivative and third derivative are given(from left to right correspondingly) Can the point x=b be an inflection point for the function.enter image description here







calculus functions






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share|cite|improve this question













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share|cite|improve this question








edited Feb 1 at 7:25







Mohan

















asked Feb 1 at 7:04









MohanMohan

285




285












  • $begingroup$
    You have answered your own question. math.stackexchange.com/questions/402459/… Yes a point where the second derivative is discontinuous at that point can be an inflection point.
    $endgroup$
    – Matthew Liu
    Feb 1 at 7:34










  • $begingroup$
    @Matthew Liu Ok.Thanks for answering.Does this mean the point x=b in the diagram can be a point of inflection for f(x) ?
    $endgroup$
    – Mohan
    Feb 1 at 7:43






  • 1




    $begingroup$
    I think it "point of inflection" is only defined as change in sign of the second derivative and that this change of sign does not need to be continuous and go through 0. But it was ages ago I even saw this expression.
    $endgroup$
    – mathreadler
    Feb 1 at 8:06












  • $begingroup$
    @mathreadler A point of inflection is a geometric property. It's a point where the tangent line crosses the graph.
    $endgroup$
    – B. Goddard
    Feb 1 at 11:39










  • $begingroup$
    @B.Goddard Hmm if you say so. I think last time I encountered the name was in high school... Definitely did not occur particularly often at university for me.
    $endgroup$
    – mathreadler
    Feb 1 at 13:12


















  • $begingroup$
    You have answered your own question. math.stackexchange.com/questions/402459/… Yes a point where the second derivative is discontinuous at that point can be an inflection point.
    $endgroup$
    – Matthew Liu
    Feb 1 at 7:34










  • $begingroup$
    @Matthew Liu Ok.Thanks for answering.Does this mean the point x=b in the diagram can be a point of inflection for f(x) ?
    $endgroup$
    – Mohan
    Feb 1 at 7:43






  • 1




    $begingroup$
    I think it "point of inflection" is only defined as change in sign of the second derivative and that this change of sign does not need to be continuous and go through 0. But it was ages ago I even saw this expression.
    $endgroup$
    – mathreadler
    Feb 1 at 8:06












  • $begingroup$
    @mathreadler A point of inflection is a geometric property. It's a point where the tangent line crosses the graph.
    $endgroup$
    – B. Goddard
    Feb 1 at 11:39










  • $begingroup$
    @B.Goddard Hmm if you say so. I think last time I encountered the name was in high school... Definitely did not occur particularly often at university for me.
    $endgroup$
    – mathreadler
    Feb 1 at 13:12
















$begingroup$
You have answered your own question. math.stackexchange.com/questions/402459/… Yes a point where the second derivative is discontinuous at that point can be an inflection point.
$endgroup$
– Matthew Liu
Feb 1 at 7:34




$begingroup$
You have answered your own question. math.stackexchange.com/questions/402459/… Yes a point where the second derivative is discontinuous at that point can be an inflection point.
$endgroup$
– Matthew Liu
Feb 1 at 7:34












$begingroup$
@Matthew Liu Ok.Thanks for answering.Does this mean the point x=b in the diagram can be a point of inflection for f(x) ?
$endgroup$
– Mohan
Feb 1 at 7:43




$begingroup$
@Matthew Liu Ok.Thanks for answering.Does this mean the point x=b in the diagram can be a point of inflection for f(x) ?
$endgroup$
– Mohan
Feb 1 at 7:43




1




1




$begingroup$
I think it "point of inflection" is only defined as change in sign of the second derivative and that this change of sign does not need to be continuous and go through 0. But it was ages ago I even saw this expression.
$endgroup$
– mathreadler
Feb 1 at 8:06






$begingroup$
I think it "point of inflection" is only defined as change in sign of the second derivative and that this change of sign does not need to be continuous and go through 0. But it was ages ago I even saw this expression.
$endgroup$
– mathreadler
Feb 1 at 8:06














$begingroup$
@mathreadler A point of inflection is a geometric property. It's a point where the tangent line crosses the graph.
$endgroup$
– B. Goddard
Feb 1 at 11:39




$begingroup$
@mathreadler A point of inflection is a geometric property. It's a point where the tangent line crosses the graph.
$endgroup$
– B. Goddard
Feb 1 at 11:39












$begingroup$
@B.Goddard Hmm if you say so. I think last time I encountered the name was in high school... Definitely did not occur particularly often at university for me.
$endgroup$
– mathreadler
Feb 1 at 13:12




$begingroup$
@B.Goddard Hmm if you say so. I think last time I encountered the name was in high school... Definitely did not occur particularly often at university for me.
$endgroup$
– mathreadler
Feb 1 at 13:12










1 Answer
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$begingroup$

The short answer is "yes." An inflection point is a point where the tangent line crosses the graph of the function. So if the tangent line is vertical at a point, then the first derivative doesn't exist and therefore the second doesn't exist.



Take $y=sqrt[3]{x}$. Then $(0,0)$ is an inflection point, but the second derivative is discontinuous there.






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    $begingroup$

    The short answer is "yes." An inflection point is a point where the tangent line crosses the graph of the function. So if the tangent line is vertical at a point, then the first derivative doesn't exist and therefore the second doesn't exist.



    Take $y=sqrt[3]{x}$. Then $(0,0)$ is an inflection point, but the second derivative is discontinuous there.






    share|cite|improve this answer









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      2












      $begingroup$

      The short answer is "yes." An inflection point is a point where the tangent line crosses the graph of the function. So if the tangent line is vertical at a point, then the first derivative doesn't exist and therefore the second doesn't exist.



      Take $y=sqrt[3]{x}$. Then $(0,0)$ is an inflection point, but the second derivative is discontinuous there.






      share|cite|improve this answer









      $endgroup$
















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        2








        2





        $begingroup$

        The short answer is "yes." An inflection point is a point where the tangent line crosses the graph of the function. So if the tangent line is vertical at a point, then the first derivative doesn't exist and therefore the second doesn't exist.



        Take $y=sqrt[3]{x}$. Then $(0,0)$ is an inflection point, but the second derivative is discontinuous there.






        share|cite|improve this answer









        $endgroup$



        The short answer is "yes." An inflection point is a point where the tangent line crosses the graph of the function. So if the tangent line is vertical at a point, then the first derivative doesn't exist and therefore the second doesn't exist.



        Take $y=sqrt[3]{x}$. Then $(0,0)$ is an inflection point, but the second derivative is discontinuous there.







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Feb 1 at 11:43









        B. GoddardB. Goddard

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