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 $left(int |xf(x)|^2dxright)^{1/2}left(int |f(x)|^2dxright)^{1/2} leq C left(int (x^2+1) |f(x)|^2dxright)^{1/2}$?
$begingroup$
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)
calculus
$endgroup$
add a comment |
$begingroup$
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)
calculus
$endgroup$
$begingroup$
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
add a comment |
$begingroup$
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)
calculus
$endgroup$
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
calculus
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
add a comment |
$begingroup$
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
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
$intlimits_{-infty}^infty e^{x^2}left(frac{d^n}{dx^n}(e^{-x^2})right)^2dx=
(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{x^2}e^{-(x+y)^2}e^{-(x+z)^2}dx)|_{y=0,z=0}$ $=(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{-(x+y+z)^2}e^{2yz}dx)|_{y=0,z=0}$
$=(frac{d^n}{dy^n}frac{d^n}{dz^n}sqrt{pi}e^{2yz})|_{y=0,z=0}=2^n n!sqrt{pi}$
(modulo mistakes that you will easily repair)
$endgroup$
$begingroup$
@MariuszIwaniuk you are right - aparently I don't know how to differentiate $exp$ :)
$endgroup$
– user8268
2 days ago
add a comment |
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
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
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
$begingroup$
$intlimits_{-infty}^infty e^{x^2}left(frac{d^n}{dx^n}(e^{-x^2})right)^2dx=
(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{x^2}e^{-(x+y)^2}e^{-(x+z)^2}dx)|_{y=0,z=0}$ $=(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{-(x+y+z)^2}e^{2yz}dx)|_{y=0,z=0}$
$=(frac{d^n}{dy^n}frac{d^n}{dz^n}sqrt{pi}e^{2yz})|_{y=0,z=0}=2^n n!sqrt{pi}$
(modulo mistakes that you will easily repair)
$endgroup$
$begingroup$
@MariuszIwaniuk you are right - aparently I don't know how to differentiate $exp$ :)
$endgroup$
– user8268
2 days ago
add a comment |
$begingroup$
$intlimits_{-infty}^infty e^{x^2}left(frac{d^n}{dx^n}(e^{-x^2})right)^2dx=
(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{x^2}e^{-(x+y)^2}e^{-(x+z)^2}dx)|_{y=0,z=0}$ $=(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{-(x+y+z)^2}e^{2yz}dx)|_{y=0,z=0}$
$=(frac{d^n}{dy^n}frac{d^n}{dz^n}sqrt{pi}e^{2yz})|_{y=0,z=0}=2^n n!sqrt{pi}$
(modulo mistakes that you will easily repair)
$endgroup$
$begingroup$
@MariuszIwaniuk you are right - aparently I don't know how to differentiate $exp$ :)
$endgroup$
– user8268
2 days ago
add a comment |
$begingroup$
$intlimits_{-infty}^infty e^{x^2}left(frac{d^n}{dx^n}(e^{-x^2})right)^2dx=
(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{x^2}e^{-(x+y)^2}e^{-(x+z)^2}dx)|_{y=0,z=0}$ $=(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{-(x+y+z)^2}e^{2yz}dx)|_{y=0,z=0}$
$=(frac{d^n}{dy^n}frac{d^n}{dz^n}sqrt{pi}e^{2yz})|_{y=0,z=0}=2^n n!sqrt{pi}$
(modulo mistakes that you will easily repair)
$endgroup$
$intlimits_{-infty}^infty e^{x^2}left(frac{d^n}{dx^n}(e^{-x^2})right)^2dx=
(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{x^2}e^{-(x+y)^2}e^{-(x+z)^2}dx)|_{y=0,z=0}$ $=(frac{d^n}{dy^n}frac{d^n}{dz^n}intlimits_{-infty}^infty e^{-(x+y+z)^2}e^{2yz}dx)|_{y=0,z=0}$
$=(frac{d^n}{dy^n}frac{d^n}{dz^n}sqrt{pi}e^{2yz})|_{y=0,z=0}=2^n n!sqrt{pi}$
(modulo mistakes that you will easily repair)
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
add a comment |
$begingroup$
@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
add a comment |
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.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
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
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
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
$begingroup$
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