Value of $intlimits_{-infty}^infty e^{x^2}left(frac{d^n}{dx^n}(e^{-x^2})right)^2dx$Show that...

Haman going to the second feast dirty

Which situations would cause a company to ground or recall a aircraft series?

Can I use a violin G string for D?

Can we track matter through time by looking at different depths in space?

Having the player face themselves after the mid-game

After `ssh` without `-X` to a machine, is it possible to change `$DISPLAY` to make it work like `ssh -X`?

What's the 'present simple' form of the word "нашла́" in 3rd person singular female?

How to resolve: Reviewer #1 says remove section X vs. Reviewer #2 says expand section X

Is it safe to abruptly remove Arduino power?

Is this Paypal Github SDK reference really a dangerous site?

How does Ehrenfest's theorem apply to the quantum harmonic oscillator?

Why is there an extra space when I type "ls" in the Desktop directory?

What problems would a superhuman have whose skin is constantly hot?

Doesn't allowing a user mode program to access kernel space memory and execute the IN and OUT instructions defeat the purpose of having CPU modes?

Is divide-by-zero a security vulnerability?

Is there a difference between equilibrium and steady state?

Why is a very small peak with larger m/z not considered to be the molecular ion?

Why do phishing e-mails use faked e-mail addresses instead of the real one?

Conservation of Mass and Energy

Did Amazon pay $0 in taxes last year?

What materials can be used to make a humanoid skin warm?

Why couldn't the separatists legally leave the Republic?

Vocabulary for giving just numbers, not a full answer

What is better: yes / no radio, or simple checkbox?



Value of $intlimits_{-infty}^infty e^{x^2}left(frac{d^n}{dx^n}(e^{-x^2})right)^2dx$


Show that $int^{infty}_{0}left(frac{sin(x)}{x}right)^2 < 2$Evaluate $int limits _{0}^{infty}lnleft({x+frac{1}{x}}right)cdotfrac{mathrm dx}{1+x^2}$Convergence of the integral $intlimits_{1}^{infty} left( frac{1}{sqrt{x}} - frac{1}{sqrt{x+3}} right) , dx$Does $int _1^{infty }left(sin left(x^2right)right)dx$ converge or diverge?Integrate $intfrac{dx}{xsqrt{x^2+1}}$Does $int _0^{infty }left(fleft(xright)+gleft(xright)right)^2dx$ converge or diverge?Evaluating $int x!left(frac1x+frac{1}{x-1}+…+frac11right)dx$does the integral $int _{1}^{infty }!{frac {sin left( cos left( x right) +sin left( xsqrt {3} right) right) }{x}}{dx}$ converges?Evaluating the integral: $intlimits_{0}^{infty}left(frac{sin(ax)}{x}right)^2 dx , a neq 0 $Is it true that $left(int |xf(x)|^2dxright)^{1/2}left(int |f(x)|^2dxright)^{1/2} leq C left(int (x^2+1) |f(x)|^2dxright)^{1/2}$?













1












$begingroup$


I need to find the value of this integral : $intlimits_{-infty}^infty e^{x^2}left(frac{d^n}{dx^n}(e^{-x^2})right)^2dx$ .



I tried to integrate by parts $intlimits_{-infty}^infty e^{x^2}left(frac{d^{n+1}}{dx^{n+1}}(e^{-x^2})right)^2dx$ but I'm stuck for the expression of the antiderivative. Any help would be greatly appreciated.



(n is a positive integer)










share|cite|improve this question











$endgroup$












  • $begingroup$
    Have you tried brute force - taking the derivative (which will be a polynomial times $e^{-x^2}$) After squaring the integrand will be another polynomial times $e^{-x^2}$, which can be integrated explicitly.
    $endgroup$
    – herb steinberg
    2 days ago












  • $begingroup$
    What is the value of $n$, or are you trying to get a general expression for all values of $n$?
    $endgroup$
    – John Omielan
    2 days ago












  • $begingroup$
    @JohnOmielan n is a positive integer, so I'm trying to get a general expression
    $endgroup$
    – Cominou
    2 days ago
















1












$begingroup$


I need to find the value of this integral : $intlimits_{-infty}^infty e^{x^2}left(frac{d^n}{dx^n}(e^{-x^2})right)^2dx$ .



I tried to integrate by parts $intlimits_{-infty}^infty e^{x^2}left(frac{d^{n+1}}{dx^{n+1}}(e^{-x^2})right)^2dx$ but I'm stuck for the expression of the antiderivative. Any help would be greatly appreciated.



(n is a positive integer)










share|cite|improve this question











$endgroup$












  • $begingroup$
    Have you tried brute force - taking the derivative (which will be a polynomial times $e^{-x^2}$) After squaring the integrand will be another polynomial times $e^{-x^2}$, which can be integrated explicitly.
    $endgroup$
    – herb steinberg
    2 days ago












  • $begingroup$
    What is the value of $n$, or are you trying to get a general expression for all values of $n$?
    $endgroup$
    – John Omielan
    2 days ago












  • $begingroup$
    @JohnOmielan n is a positive integer, so I'm trying to get a general expression
    $endgroup$
    – Cominou
    2 days ago














1












1








1





$begingroup$


I need to find the value of this integral : $intlimits_{-infty}^infty e^{x^2}left(frac{d^n}{dx^n}(e^{-x^2})right)^2dx$ .



I tried to integrate by parts $intlimits_{-infty}^infty e^{x^2}left(frac{d^{n+1}}{dx^{n+1}}(e^{-x^2})right)^2dx$ but I'm stuck for the expression of the antiderivative. Any help would be greatly appreciated.



(n is a positive integer)










share|cite|improve this question











$endgroup$




I need to find the value of this integral : $intlimits_{-infty}^infty e^{x^2}left(frac{d^n}{dx^n}(e^{-x^2})right)^2dx$ .



I tried to integrate by parts $intlimits_{-infty}^infty e^{x^2}left(frac{d^{n+1}}{dx^{n+1}}(e^{-x^2})right)^2dx$ but I'm stuck for the expression of the antiderivative. Any help would be greatly appreciated.



(n is a positive integer)







calculus






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited 2 days ago







Cominou

















asked 2 days ago









CominouCominou

364




364












  • $begingroup$
    Have you tried brute force - taking the derivative (which will be a polynomial times $e^{-x^2}$) After squaring the integrand will be another polynomial times $e^{-x^2}$, which can be integrated explicitly.
    $endgroup$
    – herb steinberg
    2 days ago












  • $begingroup$
    What is the value of $n$, or are you trying to get a general expression for all values of $n$?
    $endgroup$
    – John Omielan
    2 days ago












  • $begingroup$
    @JohnOmielan n is a positive integer, so I'm trying to get a general expression
    $endgroup$
    – Cominou
    2 days ago


















  • $begingroup$
    Have you tried brute force - taking the derivative (which will be a polynomial times $e^{-x^2}$) After squaring the integrand will be another polynomial times $e^{-x^2}$, which can be integrated explicitly.
    $endgroup$
    – herb steinberg
    2 days ago












  • $begingroup$
    What is the value of $n$, or are you trying to get a general expression for all values of $n$?
    $endgroup$
    – John Omielan
    2 days ago












  • $begingroup$
    @JohnOmielan n is a positive integer, so I'm trying to get a general expression
    $endgroup$
    – Cominou
    2 days ago
















$begingroup$
Have you tried brute force - taking the derivative (which will be a polynomial times $e^{-x^2}$) After squaring the integrand will be another polynomial times $e^{-x^2}$, which can be integrated explicitly.
$endgroup$
– herb steinberg
2 days ago






$begingroup$
Have you tried brute force - taking the derivative (which will be a polynomial times $e^{-x^2}$) After squaring the integrand will be another polynomial times $e^{-x^2}$, which can be integrated explicitly.
$endgroup$
– herb steinberg
2 days ago














$begingroup$
What is the value of $n$, or are you trying to get a general expression for all values of $n$?
$endgroup$
– John Omielan
2 days ago






$begingroup$
What is the value of $n$, or are you trying to get a general expression for all values of $n$?
$endgroup$
– John Omielan
2 days ago














$begingroup$
@JohnOmielan n is a positive integer, so I'm trying to get a general expression
$endgroup$
– Cominou
2 days ago




$begingroup$
@JohnOmielan n is a positive integer, so I'm trying to get a general expression
$endgroup$
– Cominou
2 days ago










1 Answer
1






active

oldest

votes


















3












$begingroup$

$intlimits_{-infty}^infty e^{x^2}left(frac{d^n}{dx^n}(e^{-x^2})right)^2dx=
(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{x^2}e^{-(x+y)^2}e^{-(x+z)^2}dx)|_{y=0,z=0}$
$=(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{-(x+y+z)^2}e^{2yz}dx)|_{y=0,z=0}$
$=(frac{d^n}{dy^n}frac{d^n}{dz^n}sqrt{pi}e^{2yz})|_{y=0,z=0}=2^n n!sqrt{pi}$
(modulo mistakes that you will easily repair)






share|cite|improve this answer











$endgroup$













  • $begingroup$
    @MariuszIwaniuk you are right - aparently I don't know how to differentiate $exp$ :)
    $endgroup$
    – user8268
    2 days ago











Your Answer





StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");

StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});














draft saved

draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3140372%2fvalue-of-int-limits-infty-infty-ex2-left-fracdndxne-x2-r%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown

























1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes









3












$begingroup$

$intlimits_{-infty}^infty e^{x^2}left(frac{d^n}{dx^n}(e^{-x^2})right)^2dx=
(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{x^2}e^{-(x+y)^2}e^{-(x+z)^2}dx)|_{y=0,z=0}$
$=(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{-(x+y+z)^2}e^{2yz}dx)|_{y=0,z=0}$
$=(frac{d^n}{dy^n}frac{d^n}{dz^n}sqrt{pi}e^{2yz})|_{y=0,z=0}=2^n n!sqrt{pi}$
(modulo mistakes that you will easily repair)






share|cite|improve this answer











$endgroup$













  • $begingroup$
    @MariuszIwaniuk you are right - aparently I don't know how to differentiate $exp$ :)
    $endgroup$
    – user8268
    2 days ago
















3












$begingroup$

$intlimits_{-infty}^infty e^{x^2}left(frac{d^n}{dx^n}(e^{-x^2})right)^2dx=
(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{x^2}e^{-(x+y)^2}e^{-(x+z)^2}dx)|_{y=0,z=0}$
$=(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{-(x+y+z)^2}e^{2yz}dx)|_{y=0,z=0}$
$=(frac{d^n}{dy^n}frac{d^n}{dz^n}sqrt{pi}e^{2yz})|_{y=0,z=0}=2^n n!sqrt{pi}$
(modulo mistakes that you will easily repair)






share|cite|improve this answer











$endgroup$













  • $begingroup$
    @MariuszIwaniuk you are right - aparently I don't know how to differentiate $exp$ :)
    $endgroup$
    – user8268
    2 days ago














3












3








3





$begingroup$

$intlimits_{-infty}^infty e^{x^2}left(frac{d^n}{dx^n}(e^{-x^2})right)^2dx=
(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{x^2}e^{-(x+y)^2}e^{-(x+z)^2}dx)|_{y=0,z=0}$
$=(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{-(x+y+z)^2}e^{2yz}dx)|_{y=0,z=0}$
$=(frac{d^n}{dy^n}frac{d^n}{dz^n}sqrt{pi}e^{2yz})|_{y=0,z=0}=2^n n!sqrt{pi}$
(modulo mistakes that you will easily repair)






share|cite|improve this answer











$endgroup$



$intlimits_{-infty}^infty e^{x^2}left(frac{d^n}{dx^n}(e^{-x^2})right)^2dx=
(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{x^2}e^{-(x+y)^2}e^{-(x+z)^2}dx)|_{y=0,z=0}$
$=(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{-(x+y+z)^2}e^{2yz}dx)|_{y=0,z=0}$
$=(frac{d^n}{dy^n}frac{d^n}{dz^n}sqrt{pi}e^{2yz})|_{y=0,z=0}=2^n n!sqrt{pi}$
(modulo mistakes that you will easily repair)







share|cite|improve this answer














share|cite|improve this answer



share|cite|improve this answer








edited 2 days ago

























answered 2 days ago









user8268user8268

17k12747




17k12747












  • $begingroup$
    @MariuszIwaniuk you are right - aparently I don't know how to differentiate $exp$ :)
    $endgroup$
    – user8268
    2 days ago


















  • $begingroup$
    @MariuszIwaniuk you are right - aparently I don't know how to differentiate $exp$ :)
    $endgroup$
    – user8268
    2 days ago
















$begingroup$
@MariuszIwaniuk you are right - aparently I don't know how to differentiate $exp$ :)
$endgroup$
– user8268
2 days ago




$begingroup$
@MariuszIwaniuk you are right - aparently I don't know how to differentiate $exp$ :)
$endgroup$
– user8268
2 days ago


















draft saved

draft discarded




















































Thanks for contributing an answer to Mathematics Stack Exchange!


  • Please be sure to answer the question. Provide details and share your research!

But avoid



  • Asking for help, clarification, or responding to other answers.

  • Making statements based on opinion; back them up with references or personal experience.


Use MathJax to format equations. MathJax reference.


To learn more, see our tips on writing great answers.




draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3140372%2fvalue-of-int-limits-infty-infty-ex2-left-fracdndxne-x2-r%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown





















































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown

































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown







Popular posts from this blog

Nidaros erkebispedøme

Birsay

Where did Arya get these scars? Unicorn Meta Zoo #1: Why another podcast? Announcing the arrival of Valued Associate #679: Cesar Manara Favourite questions and answers from the 1st quarter of 2019Why did Arya refuse to end it?Has the pronunciation of Arya Stark's name changed?Has Arya forgiven people?Why did Arya Stark lose her vision?Why can Arya still use the faces?Has the Narrow Sea become narrower?Does Arya Stark know how to make poisons outside of the House of Black and White?Why did Nymeria leave Arya?Why did Arya not kill the Lannister soldiers she encountered in the Riverlands?What is the current canonical age of Sansa, Bran and Arya Stark?