Write power series as rational function
I need to write the power series:
$sum_{n=1}^infty frac{1}{(x-3)^{2n-1}} - frac{1}{(x-2)^{2n-1}}$
I need to write it as a rational function. I am not sure how to go about doing this.
power-series
add a comment |
I need to write the power series:
$sum_{n=1}^infty frac{1}{(x-3)^{2n-1}} - frac{1}{(x-2)^{2n-1}}$
I need to write it as a rational function. I am not sure how to go about doing this.
power-series
add a comment |
I need to write the power series:
$sum_{n=1}^infty frac{1}{(x-3)^{2n-1}} - frac{1}{(x-2)^{2n-1}}$
I need to write it as a rational function. I am not sure how to go about doing this.
power-series
I need to write the power series:
$sum_{n=1}^infty frac{1}{(x-3)^{2n-1}} - frac{1}{(x-2)^{2n-1}}$
I need to write it as a rational function. I am not sure how to go about doing this.
power-series
power-series
asked Dec 7 at 22:39
Elijah
626
626
add a comment |
add a comment |
2 Answers
2
active
oldest
votes
In general $sum_{n=1}^inftyfrac{1}{u^{2n-1}}=frac{u}{u^2-1}$. Your expression becomes $frac{x-3}{(x-3)^2-1}-frac{x-2}{(x-2)^2-1}$$=frac{(x-3)((x-2)^2-1)-(x-2)((x-3)^2-1)}{((x-3)^2-1)((x-2)^2-1)}$
You could simplify it. Note that $|x-3|gt 1$ and $|x-2| gt 1$ required.
add a comment |
Hint:
This series has the form
$$sum_{n=1}^inftyfrac1{u^{2n-1}}-sum_{n=1}^inftyfrac1{v^{2n-1}}=frac1usum_{n=0}^inftyfrac1{(u^2)^n}-frac1vsum_{n=0}^inftyfrac1{(v^2)^n}.$$
Can you take it from here?
$$
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%2f3030449%2fwrite-power-series-as-rational-function%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
In general $sum_{n=1}^inftyfrac{1}{u^{2n-1}}=frac{u}{u^2-1}$. Your expression becomes $frac{x-3}{(x-3)^2-1}-frac{x-2}{(x-2)^2-1}$$=frac{(x-3)((x-2)^2-1)-(x-2)((x-3)^2-1)}{((x-3)^2-1)((x-2)^2-1)}$
You could simplify it. Note that $|x-3|gt 1$ and $|x-2| gt 1$ required.
add a comment |
In general $sum_{n=1}^inftyfrac{1}{u^{2n-1}}=frac{u}{u^2-1}$. Your expression becomes $frac{x-3}{(x-3)^2-1}-frac{x-2}{(x-2)^2-1}$$=frac{(x-3)((x-2)^2-1)-(x-2)((x-3)^2-1)}{((x-3)^2-1)((x-2)^2-1)}$
You could simplify it. Note that $|x-3|gt 1$ and $|x-2| gt 1$ required.
add a comment |
In general $sum_{n=1}^inftyfrac{1}{u^{2n-1}}=frac{u}{u^2-1}$. Your expression becomes $frac{x-3}{(x-3)^2-1}-frac{x-2}{(x-2)^2-1}$$=frac{(x-3)((x-2)^2-1)-(x-2)((x-3)^2-1)}{((x-3)^2-1)((x-2)^2-1)}$
You could simplify it. Note that $|x-3|gt 1$ and $|x-2| gt 1$ required.
In general $sum_{n=1}^inftyfrac{1}{u^{2n-1}}=frac{u}{u^2-1}$. Your expression becomes $frac{x-3}{(x-3)^2-1}-frac{x-2}{(x-2)^2-1}$$=frac{(x-3)((x-2)^2-1)-(x-2)((x-3)^2-1)}{((x-3)^2-1)((x-2)^2-1)}$
You could simplify it. Note that $|x-3|gt 1$ and $|x-2| gt 1$ required.
answered Dec 7 at 23:01
herb steinberg
2,4832310
2,4832310
add a comment |
add a comment |
Hint:
This series has the form
$$sum_{n=1}^inftyfrac1{u^{2n-1}}-sum_{n=1}^inftyfrac1{v^{2n-1}}=frac1usum_{n=0}^inftyfrac1{(u^2)^n}-frac1vsum_{n=0}^inftyfrac1{(v^2)^n}.$$
Can you take it from here?
$$
add a comment |
Hint:
This series has the form
$$sum_{n=1}^inftyfrac1{u^{2n-1}}-sum_{n=1}^inftyfrac1{v^{2n-1}}=frac1usum_{n=0}^inftyfrac1{(u^2)^n}-frac1vsum_{n=0}^inftyfrac1{(v^2)^n}.$$
Can you take it from here?
$$
add a comment |
Hint:
This series has the form
$$sum_{n=1}^inftyfrac1{u^{2n-1}}-sum_{n=1}^inftyfrac1{v^{2n-1}}=frac1usum_{n=0}^inftyfrac1{(u^2)^n}-frac1vsum_{n=0}^inftyfrac1{(v^2)^n}.$$
Can you take it from here?
$$
Hint:
This series has the form
$$sum_{n=1}^inftyfrac1{u^{2n-1}}-sum_{n=1}^inftyfrac1{v^{2n-1}}=frac1usum_{n=0}^inftyfrac1{(u^2)^n}-frac1vsum_{n=0}^inftyfrac1{(v^2)^n}.$$
Can you take it from here?
$$
answered Dec 7 at 22:51
Bernard
118k638112
118k638112
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.
Some of your past answers have not been well-received, and you're in danger of being blocked from answering.
Please pay close attention to the following guidance:
- 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.
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%2f3030449%2fwrite-power-series-as-rational-function%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