Help rearranging algebraic expression?!
$begingroup$
In the following relationship x and $delta_S$ are unknowns:
$$delta_f = delta_S-(delta_S-delta_o)expleft[-(1+mx)frac{It}{V}right]$$
I need to solve for x and have the following relationship for $delta_S$:
$$delta_S =frac{delta_{in}+mxdelta^*}{1+mx}$$
Therefore: $$delta_f = bigg(frac{(delta_{in}+mxdelta^*)}{(1+mx)}bigg)-bigg(frac{(delta_{in}+mxdelta^*)}{(1+mx)}-delta_ibigg)expbigg[-(1+mx)frac{It}{V}bigg]$$
Honestly I have no idea where to begin isolating x once I start taking the natural log...
logarithms exponential-function factoring
$endgroup$
add a comment |
$begingroup$
In the following relationship x and $delta_S$ are unknowns:
$$delta_f = delta_S-(delta_S-delta_o)expleft[-(1+mx)frac{It}{V}right]$$
I need to solve for x and have the following relationship for $delta_S$:
$$delta_S =frac{delta_{in}+mxdelta^*}{1+mx}$$
Therefore: $$delta_f = bigg(frac{(delta_{in}+mxdelta^*)}{(1+mx)}bigg)-bigg(frac{(delta_{in}+mxdelta^*)}{(1+mx)}-delta_ibigg)expbigg[-(1+mx)frac{It}{V}bigg]$$
Honestly I have no idea where to begin isolating x once I start taking the natural log...
logarithms exponential-function factoring
$endgroup$
add a comment |
$begingroup$
In the following relationship x and $delta_S$ are unknowns:
$$delta_f = delta_S-(delta_S-delta_o)expleft[-(1+mx)frac{It}{V}right]$$
I need to solve for x and have the following relationship for $delta_S$:
$$delta_S =frac{delta_{in}+mxdelta^*}{1+mx}$$
Therefore: $$delta_f = bigg(frac{(delta_{in}+mxdelta^*)}{(1+mx)}bigg)-bigg(frac{(delta_{in}+mxdelta^*)}{(1+mx)}-delta_ibigg)expbigg[-(1+mx)frac{It}{V}bigg]$$
Honestly I have no idea where to begin isolating x once I start taking the natural log...
logarithms exponential-function factoring
$endgroup$
In the following relationship x and $delta_S$ are unknowns:
$$delta_f = delta_S-(delta_S-delta_o)expleft[-(1+mx)frac{It}{V}right]$$
I need to solve for x and have the following relationship for $delta_S$:
$$delta_S =frac{delta_{in}+mxdelta^*}{1+mx}$$
Therefore: $$delta_f = bigg(frac{(delta_{in}+mxdelta^*)}{(1+mx)}bigg)-bigg(frac{(delta_{in}+mxdelta^*)}{(1+mx)}-delta_ibigg)expbigg[-(1+mx)frac{It}{V}bigg]$$
Honestly I have no idea where to begin isolating x once I start taking the natural log...
logarithms exponential-function factoring
logarithms exponential-function factoring
edited Jan 19 at 1:58


Larry
2,41331129
2,41331129
asked Jan 19 at 0:51
spencerchadspencerchad
82
82
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
You cannot isolate $x$ and you will need some numerical method.
If I had to do it, I would define $y=(1+mx)$ to make
$$delta_f = delta_S-(delta_S-delta_o)expleft[-yfrac{It}{V}right]$$
$$delta_S =frac{delta_{in}+mxdelta^*}{1+mx}=frac{delta_{in}-delta^*+ydelta^*}{y}=delta^*+frac{delta_{in}-delta^*}y$$ Use Newton method.
In fact, I suppose that there could be an "explicit" solution in terms of the generalized Lambert function (have a look at equation $(4)$ in the paper).
$endgroup$
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%2f3078914%2fhelp-rearranging-algebraic-expression%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
$begingroup$
You cannot isolate $x$ and you will need some numerical method.
If I had to do it, I would define $y=(1+mx)$ to make
$$delta_f = delta_S-(delta_S-delta_o)expleft[-yfrac{It}{V}right]$$
$$delta_S =frac{delta_{in}+mxdelta^*}{1+mx}=frac{delta_{in}-delta^*+ydelta^*}{y}=delta^*+frac{delta_{in}-delta^*}y$$ Use Newton method.
In fact, I suppose that there could be an "explicit" solution in terms of the generalized Lambert function (have a look at equation $(4)$ in the paper).
$endgroup$
add a comment |
$begingroup$
You cannot isolate $x$ and you will need some numerical method.
If I had to do it, I would define $y=(1+mx)$ to make
$$delta_f = delta_S-(delta_S-delta_o)expleft[-yfrac{It}{V}right]$$
$$delta_S =frac{delta_{in}+mxdelta^*}{1+mx}=frac{delta_{in}-delta^*+ydelta^*}{y}=delta^*+frac{delta_{in}-delta^*}y$$ Use Newton method.
In fact, I suppose that there could be an "explicit" solution in terms of the generalized Lambert function (have a look at equation $(4)$ in the paper).
$endgroup$
add a comment |
$begingroup$
You cannot isolate $x$ and you will need some numerical method.
If I had to do it, I would define $y=(1+mx)$ to make
$$delta_f = delta_S-(delta_S-delta_o)expleft[-yfrac{It}{V}right]$$
$$delta_S =frac{delta_{in}+mxdelta^*}{1+mx}=frac{delta_{in}-delta^*+ydelta^*}{y}=delta^*+frac{delta_{in}-delta^*}y$$ Use Newton method.
In fact, I suppose that there could be an "explicit" solution in terms of the generalized Lambert function (have a look at equation $(4)$ in the paper).
$endgroup$
You cannot isolate $x$ and you will need some numerical method.
If I had to do it, I would define $y=(1+mx)$ to make
$$delta_f = delta_S-(delta_S-delta_o)expleft[-yfrac{It}{V}right]$$
$$delta_S =frac{delta_{in}+mxdelta^*}{1+mx}=frac{delta_{in}-delta^*+ydelta^*}{y}=delta^*+frac{delta_{in}-delta^*}y$$ Use Newton method.
In fact, I suppose that there could be an "explicit" solution in terms of the generalized Lambert function (have a look at equation $(4)$ in the paper).
answered Jan 19 at 4:18
Claude LeiboviciClaude Leibovici
123k1157134
123k1157134
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%2f3078914%2fhelp-rearranging-algebraic-expression%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