How many solutions do $x^{p-1} equiv 1 pmod p$ and $x^{p-1} equiv 2 pmod p$ have?
This is my first post so I apologize for any kind of error.
I'm preparing a magistral degree exam in number theory, and I'm performing some exercise.
I'm asking here this question: how can I prove how many solutions there are for $x^{p-1} equiv 1pmod p$ and $x^{p-1} equiv 2 pmod p$?
Edit: $p$ is an odd prime.
elementary-number-theory modular-arithmetic
add a comment |
This is my first post so I apologize for any kind of error.
I'm preparing a magistral degree exam in number theory, and I'm performing some exercise.
I'm asking here this question: how can I prove how many solutions there are for $x^{p-1} equiv 1pmod p$ and $x^{p-1} equiv 2 pmod p$?
Edit: $p$ is an odd prime.
elementary-number-theory modular-arithmetic
Welcome to MSE. Your question is phrased as an isolated problem, without any further information or context. This does not match many users' quality standards, so it may attract downvotes, or be put on hold. To prevent that, please edit the question. This will help you recognise and resolve the issues. Concretely: please provide context, and include your work and thoughts on the problem. These changes can help in formulating more appropriate answers.
– José Carlos Santos
Nov 26 at 9:15
@Alessar: You may take example for $p$ say $p=5$ to get an intuitive understanding.
– Yadati Kiran
Nov 26 at 9:32
add a comment |
This is my first post so I apologize for any kind of error.
I'm preparing a magistral degree exam in number theory, and I'm performing some exercise.
I'm asking here this question: how can I prove how many solutions there are for $x^{p-1} equiv 1pmod p$ and $x^{p-1} equiv 2 pmod p$?
Edit: $p$ is an odd prime.
elementary-number-theory modular-arithmetic
This is my first post so I apologize for any kind of error.
I'm preparing a magistral degree exam in number theory, and I'm performing some exercise.
I'm asking here this question: how can I prove how many solutions there are for $x^{p-1} equiv 1pmod p$ and $x^{p-1} equiv 2 pmod p$?
Edit: $p$ is an odd prime.
elementary-number-theory modular-arithmetic
elementary-number-theory modular-arithmetic
edited Nov 26 at 9:42
Batominovski
33.7k33292
33.7k33292
asked Nov 26 at 9:07
Alessar
19613
19613
Welcome to MSE. Your question is phrased as an isolated problem, without any further information or context. This does not match many users' quality standards, so it may attract downvotes, or be put on hold. To prevent that, please edit the question. This will help you recognise and resolve the issues. Concretely: please provide context, and include your work and thoughts on the problem. These changes can help in formulating more appropriate answers.
– José Carlos Santos
Nov 26 at 9:15
@Alessar: You may take example for $p$ say $p=5$ to get an intuitive understanding.
– Yadati Kiran
Nov 26 at 9:32
add a comment |
Welcome to MSE. Your question is phrased as an isolated problem, without any further information or context. This does not match many users' quality standards, so it may attract downvotes, or be put on hold. To prevent that, please edit the question. This will help you recognise and resolve the issues. Concretely: please provide context, and include your work and thoughts on the problem. These changes can help in formulating more appropriate answers.
– José Carlos Santos
Nov 26 at 9:15
@Alessar: You may take example for $p$ say $p=5$ to get an intuitive understanding.
– Yadati Kiran
Nov 26 at 9:32
Welcome to MSE. Your question is phrased as an isolated problem, without any further information or context. This does not match many users' quality standards, so it may attract downvotes, or be put on hold. To prevent that, please edit the question. This will help you recognise and resolve the issues. Concretely: please provide context, and include your work and thoughts on the problem. These changes can help in formulating more appropriate answers.
– José Carlos Santos
Nov 26 at 9:15
Welcome to MSE. Your question is phrased as an isolated problem, without any further information or context. This does not match many users' quality standards, so it may attract downvotes, or be put on hold. To prevent that, please edit the question. This will help you recognise and resolve the issues. Concretely: please provide context, and include your work and thoughts on the problem. These changes can help in formulating more appropriate answers.
– José Carlos Santos
Nov 26 at 9:15
@Alessar: You may take example for $p$ say $p=5$ to get an intuitive understanding.
– Yadati Kiran
Nov 26 at 9:32
@Alessar: You may take example for $p$ say $p=5$ to get an intuitive understanding.
– Yadati Kiran
Nov 26 at 9:32
add a comment |
1 Answer
1
active
oldest
votes
Do you know Fermat‘s little theorem?
Consider the multiplicative group $Bbb Z^times_p$.
Yes I know it, this is the same as consider x^{p} equiv x(mod p), but for the second questions I'm really stuck
– Alessar
Nov 26 at 9:31
2
If you know Fermat's Little Theorem, then you would know that, if $p$ is a prime natural number and $x$ is an integer such that $pnmid x$, then $x^{p-1}equiv 1pmod{p}$. Thus, unless $p=2$, $x^{p-1}equiv 2pmod{p}$ has no solution.
– Batominovski
Nov 26 at 9:40
Thank you so much, it's the first time I study number theory
– Alessar
Nov 26 at 9:44
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%2f3014080%2fhow-many-solutions-do-xp-1-equiv-1-pmod-p-and-xp-1-equiv-2-pmod-p%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
Do you know Fermat‘s little theorem?
Consider the multiplicative group $Bbb Z^times_p$.
Yes I know it, this is the same as consider x^{p} equiv x(mod p), but for the second questions I'm really stuck
– Alessar
Nov 26 at 9:31
2
If you know Fermat's Little Theorem, then you would know that, if $p$ is a prime natural number and $x$ is an integer such that $pnmid x$, then $x^{p-1}equiv 1pmod{p}$. Thus, unless $p=2$, $x^{p-1}equiv 2pmod{p}$ has no solution.
– Batominovski
Nov 26 at 9:40
Thank you so much, it's the first time I study number theory
– Alessar
Nov 26 at 9:44
add a comment |
Do you know Fermat‘s little theorem?
Consider the multiplicative group $Bbb Z^times_p$.
Yes I know it, this is the same as consider x^{p} equiv x(mod p), but for the second questions I'm really stuck
– Alessar
Nov 26 at 9:31
2
If you know Fermat's Little Theorem, then you would know that, if $p$ is a prime natural number and $x$ is an integer such that $pnmid x$, then $x^{p-1}equiv 1pmod{p}$. Thus, unless $p=2$, $x^{p-1}equiv 2pmod{p}$ has no solution.
– Batominovski
Nov 26 at 9:40
Thank you so much, it's the first time I study number theory
– Alessar
Nov 26 at 9:44
add a comment |
Do you know Fermat‘s little theorem?
Consider the multiplicative group $Bbb Z^times_p$.
Do you know Fermat‘s little theorem?
Consider the multiplicative group $Bbb Z^times_p$.
answered Nov 26 at 9:12
Lukas Kofler
1,3552519
1,3552519
Yes I know it, this is the same as consider x^{p} equiv x(mod p), but for the second questions I'm really stuck
– Alessar
Nov 26 at 9:31
2
If you know Fermat's Little Theorem, then you would know that, if $p$ is a prime natural number and $x$ is an integer such that $pnmid x$, then $x^{p-1}equiv 1pmod{p}$. Thus, unless $p=2$, $x^{p-1}equiv 2pmod{p}$ has no solution.
– Batominovski
Nov 26 at 9:40
Thank you so much, it's the first time I study number theory
– Alessar
Nov 26 at 9:44
add a comment |
Yes I know it, this is the same as consider x^{p} equiv x(mod p), but for the second questions I'm really stuck
– Alessar
Nov 26 at 9:31
2
If you know Fermat's Little Theorem, then you would know that, if $p$ is a prime natural number and $x$ is an integer such that $pnmid x$, then $x^{p-1}equiv 1pmod{p}$. Thus, unless $p=2$, $x^{p-1}equiv 2pmod{p}$ has no solution.
– Batominovski
Nov 26 at 9:40
Thank you so much, it's the first time I study number theory
– Alessar
Nov 26 at 9:44
Yes I know it, this is the same as consider x^{p} equiv x(mod p), but for the second questions I'm really stuck
– Alessar
Nov 26 at 9:31
Yes I know it, this is the same as consider x^{p} equiv x(mod p), but for the second questions I'm really stuck
– Alessar
Nov 26 at 9:31
2
2
If you know Fermat's Little Theorem, then you would know that, if $p$ is a prime natural number and $x$ is an integer such that $pnmid x$, then $x^{p-1}equiv 1pmod{p}$. Thus, unless $p=2$, $x^{p-1}equiv 2pmod{p}$ has no solution.
– Batominovski
Nov 26 at 9:40
If you know Fermat's Little Theorem, then you would know that, if $p$ is a prime natural number and $x$ is an integer such that $pnmid x$, then $x^{p-1}equiv 1pmod{p}$. Thus, unless $p=2$, $x^{p-1}equiv 2pmod{p}$ has no solution.
– Batominovski
Nov 26 at 9:40
Thank you so much, it's the first time I study number theory
– Alessar
Nov 26 at 9:44
Thank you so much, it's the first time I study number theory
– Alessar
Nov 26 at 9:44
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%2f3014080%2fhow-many-solutions-do-xp-1-equiv-1-pmod-p-and-xp-1-equiv-2-pmod-p%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
Welcome to MSE. Your question is phrased as an isolated problem, without any further information or context. This does not match many users' quality standards, so it may attract downvotes, or be put on hold. To prevent that, please edit the question. This will help you recognise and resolve the issues. Concretely: please provide context, and include your work and thoughts on the problem. These changes can help in formulating more appropriate answers.
– José Carlos Santos
Nov 26 at 9:15
@Alessar: You may take example for $p$ say $p=5$ to get an intuitive understanding.
– Yadati Kiran
Nov 26 at 9:32