A problem of a linear ODE with order $n$
$begingroup$
Is there an algorithm to solve this EDO in $mathbb{R}$?
begin{equation}
x^{(n)}(t) + x^{(n-1)}(t) + cdots + x''(t) + x'(t) + x(t) = 0
end{equation}
Or a more general ODE:
begin{equation}
sum_{k=0}^{n}a_kx^{(k)}(t) = f(t)
end{equation}
With ${a_k}_{kinmathbb{N}}$ a sucession belonging to $mathbb{R}$. I don't how to start.
ordinary-differential-equations
$endgroup$
add a comment |
$begingroup$
Is there an algorithm to solve this EDO in $mathbb{R}$?
begin{equation}
x^{(n)}(t) + x^{(n-1)}(t) + cdots + x''(t) + x'(t) + x(t) = 0
end{equation}
Or a more general ODE:
begin{equation}
sum_{k=0}^{n}a_kx^{(k)}(t) = f(t)
end{equation}
With ${a_k}_{kinmathbb{N}}$ a sucession belonging to $mathbb{R}$. I don't how to start.
ordinary-differential-equations
$endgroup$
1
$begingroup$
This is probably the most "standard" $n$-th order ODE. Why is it weird?
$endgroup$
– Arctic Char
Jan 1 at 3:27
$begingroup$
@ArcticChar You are right, fixed
$endgroup$
– El Pasta
Jan 1 at 3:28
add a comment |
$begingroup$
Is there an algorithm to solve this EDO in $mathbb{R}$?
begin{equation}
x^{(n)}(t) + x^{(n-1)}(t) + cdots + x''(t) + x'(t) + x(t) = 0
end{equation}
Or a more general ODE:
begin{equation}
sum_{k=0}^{n}a_kx^{(k)}(t) = f(t)
end{equation}
With ${a_k}_{kinmathbb{N}}$ a sucession belonging to $mathbb{R}$. I don't how to start.
ordinary-differential-equations
$endgroup$
Is there an algorithm to solve this EDO in $mathbb{R}$?
begin{equation}
x^{(n)}(t) + x^{(n-1)}(t) + cdots + x''(t) + x'(t) + x(t) = 0
end{equation}
Or a more general ODE:
begin{equation}
sum_{k=0}^{n}a_kx^{(k)}(t) = f(t)
end{equation}
With ${a_k}_{kinmathbb{N}}$ a sucession belonging to $mathbb{R}$. I don't how to start.
ordinary-differential-equations
ordinary-differential-equations
edited Jan 1 at 3:29
El Pasta
asked Jan 1 at 3:01
El PastaEl Pasta
46015
46015
1
$begingroup$
This is probably the most "standard" $n$-th order ODE. Why is it weird?
$endgroup$
– Arctic Char
Jan 1 at 3:27
$begingroup$
@ArcticChar You are right, fixed
$endgroup$
– El Pasta
Jan 1 at 3:28
add a comment |
1
$begingroup$
This is probably the most "standard" $n$-th order ODE. Why is it weird?
$endgroup$
– Arctic Char
Jan 1 at 3:27
$begingroup$
@ArcticChar You are right, fixed
$endgroup$
– El Pasta
Jan 1 at 3:28
1
1
$begingroup$
This is probably the most "standard" $n$-th order ODE. Why is it weird?
$endgroup$
– Arctic Char
Jan 1 at 3:27
$begingroup$
This is probably the most "standard" $n$-th order ODE. Why is it weird?
$endgroup$
– Arctic Char
Jan 1 at 3:27
$begingroup$
@ArcticChar You are right, fixed
$endgroup$
– El Pasta
Jan 1 at 3:28
$begingroup$
@ArcticChar You are right, fixed
$endgroup$
– El Pasta
Jan 1 at 3:28
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
A common method for linear ODE like this is to assume that the solution takes the form $y(t) = e^{lambda t}$. This will give you a polynomial in $lambda$, the solutions of which are called the eigenvalues. The solution will be something like
$$y(t) = c_1e^{lambda_1 t}+c_2e^{lambda_2 t} + ... + c_ne^{lambda_n t}.$$
For any complex $lambda$, you will have some portion of your solution being sinusoidal. You also need to adjust your solution for any repeated $lambda$.
$endgroup$
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%2f3058190%2fa-problem-of-a-linear-ode-with-order-n%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
$begingroup$
A common method for linear ODE like this is to assume that the solution takes the form $y(t) = e^{lambda t}$. This will give you a polynomial in $lambda$, the solutions of which are called the eigenvalues. The solution will be something like
$$y(t) = c_1e^{lambda_1 t}+c_2e^{lambda_2 t} + ... + c_ne^{lambda_n t}.$$
For any complex $lambda$, you will have some portion of your solution being sinusoidal. You also need to adjust your solution for any repeated $lambda$.
$endgroup$
add a comment |
$begingroup$
A common method for linear ODE like this is to assume that the solution takes the form $y(t) = e^{lambda t}$. This will give you a polynomial in $lambda$, the solutions of which are called the eigenvalues. The solution will be something like
$$y(t) = c_1e^{lambda_1 t}+c_2e^{lambda_2 t} + ... + c_ne^{lambda_n t}.$$
For any complex $lambda$, you will have some portion of your solution being sinusoidal. You also need to adjust your solution for any repeated $lambda$.
$endgroup$
add a comment |
$begingroup$
A common method for linear ODE like this is to assume that the solution takes the form $y(t) = e^{lambda t}$. This will give you a polynomial in $lambda$, the solutions of which are called the eigenvalues. The solution will be something like
$$y(t) = c_1e^{lambda_1 t}+c_2e^{lambda_2 t} + ... + c_ne^{lambda_n t}.$$
For any complex $lambda$, you will have some portion of your solution being sinusoidal. You also need to adjust your solution for any repeated $lambda$.
$endgroup$
A common method for linear ODE like this is to assume that the solution takes the form $y(t) = e^{lambda t}$. This will give you a polynomial in $lambda$, the solutions of which are called the eigenvalues. The solution will be something like
$$y(t) = c_1e^{lambda_1 t}+c_2e^{lambda_2 t} + ... + c_ne^{lambda_n t}.$$
For any complex $lambda$, you will have some portion of your solution being sinusoidal. You also need to adjust your solution for any repeated $lambda$.
answered Jan 1 at 3:16
D.B.D.B.
1,2028
1,2028
add a comment |
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%2f3058190%2fa-problem-of-a-linear-ode-with-order-n%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
1
$begingroup$
This is probably the most "standard" $n$-th order ODE. Why is it weird?
$endgroup$
– Arctic Char
Jan 1 at 3:27
$begingroup$
@ArcticChar You are right, fixed
$endgroup$
– El Pasta
Jan 1 at 3:28