Trying to extend distributive property of modulo operation to real numbers












0












$begingroup$


Here Wikipedia states that modulo operation is distributive:
$$a cdot b mod n = (a mod n)cdot (b mod n) mod n$$
Which is true for every natural number. Unfortunately it is not for rational ones:
given$q in Bbb Q, n in Bbb Z, qcdot n notin Bbb Z $.
$$qcdot n mod 1 ne 0 $$
$$ left{ begin{array}{c}q mod 1ne0\n mod 1 = 0 end{array}right.$$
Therefore $$(q mod 1)cdot(n mod 1)=0 $$
I was wondering if you guys have any idea on how to extend this very property to real numbers (or rational ones).










share|cite|improve this question









$endgroup$












  • $begingroup$
    you can't, not if you mean real distributivity. The reason for that is that the modulo construction on integers is actually taking the quotient by "nice" subgroups which are closed under arbitrary multiplication (ideals). sadly however $mathbb{Q}$ is a field, and hence has no nontrivial prime ideals. (this corresponds precisely to your problem above, that as soon as you have a number vanishing in modulo, $1$ has to vanish as well)
    $endgroup$
    – Enkidu
    Dec 18 '18 at 14:28
















0












$begingroup$


Here Wikipedia states that modulo operation is distributive:
$$a cdot b mod n = (a mod n)cdot (b mod n) mod n$$
Which is true for every natural number. Unfortunately it is not for rational ones:
given$q in Bbb Q, n in Bbb Z, qcdot n notin Bbb Z $.
$$qcdot n mod 1 ne 0 $$
$$ left{ begin{array}{c}q mod 1ne0\n mod 1 = 0 end{array}right.$$
Therefore $$(q mod 1)cdot(n mod 1)=0 $$
I was wondering if you guys have any idea on how to extend this very property to real numbers (or rational ones).










share|cite|improve this question









$endgroup$












  • $begingroup$
    you can't, not if you mean real distributivity. The reason for that is that the modulo construction on integers is actually taking the quotient by "nice" subgroups which are closed under arbitrary multiplication (ideals). sadly however $mathbb{Q}$ is a field, and hence has no nontrivial prime ideals. (this corresponds precisely to your problem above, that as soon as you have a number vanishing in modulo, $1$ has to vanish as well)
    $endgroup$
    – Enkidu
    Dec 18 '18 at 14:28














0












0








0





$begingroup$


Here Wikipedia states that modulo operation is distributive:
$$a cdot b mod n = (a mod n)cdot (b mod n) mod n$$
Which is true for every natural number. Unfortunately it is not for rational ones:
given$q in Bbb Q, n in Bbb Z, qcdot n notin Bbb Z $.
$$qcdot n mod 1 ne 0 $$
$$ left{ begin{array}{c}q mod 1ne0\n mod 1 = 0 end{array}right.$$
Therefore $$(q mod 1)cdot(n mod 1)=0 $$
I was wondering if you guys have any idea on how to extend this very property to real numbers (or rational ones).










share|cite|improve this question









$endgroup$




Here Wikipedia states that modulo operation is distributive:
$$a cdot b mod n = (a mod n)cdot (b mod n) mod n$$
Which is true for every natural number. Unfortunately it is not for rational ones:
given$q in Bbb Q, n in Bbb Z, qcdot n notin Bbb Z $.
$$qcdot n mod 1 ne 0 $$
$$ left{ begin{array}{c}q mod 1ne0\n mod 1 = 0 end{array}right.$$
Therefore $$(q mod 1)cdot(n mod 1)=0 $$
I was wondering if you guys have any idea on how to extend this very property to real numbers (or rational ones).







modular-arithmetic real-numbers irrational-numbers integers






share|cite|improve this question













share|cite|improve this question











share|cite|improve this question




share|cite|improve this question










asked Dec 18 '18 at 12:19









Lyn CassidyLyn Cassidy

436




436












  • $begingroup$
    you can't, not if you mean real distributivity. The reason for that is that the modulo construction on integers is actually taking the quotient by "nice" subgroups which are closed under arbitrary multiplication (ideals). sadly however $mathbb{Q}$ is a field, and hence has no nontrivial prime ideals. (this corresponds precisely to your problem above, that as soon as you have a number vanishing in modulo, $1$ has to vanish as well)
    $endgroup$
    – Enkidu
    Dec 18 '18 at 14:28


















  • $begingroup$
    you can't, not if you mean real distributivity. The reason for that is that the modulo construction on integers is actually taking the quotient by "nice" subgroups which are closed under arbitrary multiplication (ideals). sadly however $mathbb{Q}$ is a field, and hence has no nontrivial prime ideals. (this corresponds precisely to your problem above, that as soon as you have a number vanishing in modulo, $1$ has to vanish as well)
    $endgroup$
    – Enkidu
    Dec 18 '18 at 14:28
















$begingroup$
you can't, not if you mean real distributivity. The reason for that is that the modulo construction on integers is actually taking the quotient by "nice" subgroups which are closed under arbitrary multiplication (ideals). sadly however $mathbb{Q}$ is a field, and hence has no nontrivial prime ideals. (this corresponds precisely to your problem above, that as soon as you have a number vanishing in modulo, $1$ has to vanish as well)
$endgroup$
– Enkidu
Dec 18 '18 at 14:28




$begingroup$
you can't, not if you mean real distributivity. The reason for that is that the modulo construction on integers is actually taking the quotient by "nice" subgroups which are closed under arbitrary multiplication (ideals). sadly however $mathbb{Q}$ is a field, and hence has no nontrivial prime ideals. (this corresponds precisely to your problem above, that as soon as you have a number vanishing in modulo, $1$ has to vanish as well)
$endgroup$
– Enkidu
Dec 18 '18 at 14:28










0






active

oldest

votes











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
});


}
});














draft saved

draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3045107%2ftrying-to-extend-distributive-property-of-modulo-operation-to-real-numbers%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown

























0






active

oldest

votes








0






active

oldest

votes









active

oldest

votes






active

oldest

votes
















draft saved

draft discarded




















































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.




draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3045107%2ftrying-to-extend-distributive-property-of-modulo-operation-to-real-numbers%23new-answer', 'question_page');
}
);

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







Popular posts from this blog

Plaza Victoria

Puebla de Zaragoza

Musa