Line Integral Shift
$begingroup$
How does the integration identity $int_{a + c}^{b + c} f(x - c) dx = int_a^b f(x) dx$ extend to line integrals? Would a line integral of $f(x(t), y(t))$ shifted to $a + c leq t leq b + c$ become $f(x(t) - c, y(t) - c)$, $f(x(t - c), y(t - c))$, or something different? Does this depend on whether the line integral is with respect to $x$ or $y$ (scalar field), arclength (scalar field), or $vec r$ (vector field), and in each case, which aspects of the problem's geometry would be altered by the shift, and which would be invariant?
calculus integration geometry multivariable-calculus
$endgroup$
add a comment |
$begingroup$
How does the integration identity $int_{a + c}^{b + c} f(x - c) dx = int_a^b f(x) dx$ extend to line integrals? Would a line integral of $f(x(t), y(t))$ shifted to $a + c leq t leq b + c$ become $f(x(t) - c, y(t) - c)$, $f(x(t - c), y(t - c))$, or something different? Does this depend on whether the line integral is with respect to $x$ or $y$ (scalar field), arclength (scalar field), or $vec r$ (vector field), and in each case, which aspects of the problem's geometry would be altered by the shift, and which would be invariant?
calculus integration geometry multivariable-calculus
$endgroup$
add a comment |
$begingroup$
How does the integration identity $int_{a + c}^{b + c} f(x - c) dx = int_a^b f(x) dx$ extend to line integrals? Would a line integral of $f(x(t), y(t))$ shifted to $a + c leq t leq b + c$ become $f(x(t) - c, y(t) - c)$, $f(x(t - c), y(t - c))$, or something different? Does this depend on whether the line integral is with respect to $x$ or $y$ (scalar field), arclength (scalar field), or $vec r$ (vector field), and in each case, which aspects of the problem's geometry would be altered by the shift, and which would be invariant?
calculus integration geometry multivariable-calculus
$endgroup$
How does the integration identity $int_{a + c}^{b + c} f(x - c) dx = int_a^b f(x) dx$ extend to line integrals? Would a line integral of $f(x(t), y(t))$ shifted to $a + c leq t leq b + c$ become $f(x(t) - c, y(t) - c)$, $f(x(t - c), y(t - c))$, or something different? Does this depend on whether the line integral is with respect to $x$ or $y$ (scalar field), arclength (scalar field), or $vec r$ (vector field), and in each case, which aspects of the problem's geometry would be altered by the shift, and which would be invariant?
calculus integration geometry multivariable-calculus
calculus integration geometry multivariable-calculus
asked Jan 7 at 20:53
user10478user10478
453211
453211
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
It should become $f(x(t-c),y(t-c))$. The line integral would be with respect to the variable that parameterises the line, namely $t$.
$$int_{tin[a,b]}f(x(t),y(t))mathrm dt=int_{tin[a+c,b+c]}f(x(t-c),y(t-c))mathrm dt$$
The reason why this works is because, as with the one dimensional example, changing the variables in this way keeps the path that we integrate along the same.
In the notation $int_{mathcal C}f(vec x),mathrm ds$, this choice of parameterisation is hidden, so no change of variables happen here.
$endgroup$
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%2f3065476%2fline-integral-shift%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
$begingroup$
It should become $f(x(t-c),y(t-c))$. The line integral would be with respect to the variable that parameterises the line, namely $t$.
$$int_{tin[a,b]}f(x(t),y(t))mathrm dt=int_{tin[a+c,b+c]}f(x(t-c),y(t-c))mathrm dt$$
The reason why this works is because, as with the one dimensional example, changing the variables in this way keeps the path that we integrate along the same.
In the notation $int_{mathcal C}f(vec x),mathrm ds$, this choice of parameterisation is hidden, so no change of variables happen here.
$endgroup$
add a comment |
$begingroup$
It should become $f(x(t-c),y(t-c))$. The line integral would be with respect to the variable that parameterises the line, namely $t$.
$$int_{tin[a,b]}f(x(t),y(t))mathrm dt=int_{tin[a+c,b+c]}f(x(t-c),y(t-c))mathrm dt$$
The reason why this works is because, as with the one dimensional example, changing the variables in this way keeps the path that we integrate along the same.
In the notation $int_{mathcal C}f(vec x),mathrm ds$, this choice of parameterisation is hidden, so no change of variables happen here.
$endgroup$
add a comment |
$begingroup$
It should become $f(x(t-c),y(t-c))$. The line integral would be with respect to the variable that parameterises the line, namely $t$.
$$int_{tin[a,b]}f(x(t),y(t))mathrm dt=int_{tin[a+c,b+c]}f(x(t-c),y(t-c))mathrm dt$$
The reason why this works is because, as with the one dimensional example, changing the variables in this way keeps the path that we integrate along the same.
In the notation $int_{mathcal C}f(vec x),mathrm ds$, this choice of parameterisation is hidden, so no change of variables happen here.
$endgroup$
It should become $f(x(t-c),y(t-c))$. The line integral would be with respect to the variable that parameterises the line, namely $t$.
$$int_{tin[a,b]}f(x(t),y(t))mathrm dt=int_{tin[a+c,b+c]}f(x(t-c),y(t-c))mathrm dt$$
The reason why this works is because, as with the one dimensional example, changing the variables in this way keeps the path that we integrate along the same.
In the notation $int_{mathcal C}f(vec x),mathrm ds$, this choice of parameterisation is hidden, so no change of variables happen here.
answered Jan 7 at 21:45
John DoeJohn Doe
11.1k11238
11.1k11238
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%2f3065476%2fline-integral-shift%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