Is ∅ ∈ { {∅} } true?
$begingroup$
If $ {emptyset} ∈ {emptyset,{emptyset}} $ is true, does it mean this $ emptyset in {{emptyset}} $ true ? If it is not, why it is false?
Also, does $ {{emptyset}}$ mean ${emptyset,{emptyset,{emptyset}}}$ ?
elementary-set-theory
New contributor
$endgroup$
add a comment |
$begingroup$
If $ {emptyset} ∈ {emptyset,{emptyset}} $ is true, does it mean this $ emptyset in {{emptyset}} $ true ? If it is not, why it is false?
Also, does $ {{emptyset}}$ mean ${emptyset,{emptyset,{emptyset}}}$ ?
elementary-set-theory
New contributor
$endgroup$
add a comment |
$begingroup$
If $ {emptyset} ∈ {emptyset,{emptyset}} $ is true, does it mean this $ emptyset in {{emptyset}} $ true ? If it is not, why it is false?
Also, does $ {{emptyset}}$ mean ${emptyset,{emptyset,{emptyset}}}$ ?
elementary-set-theory
New contributor
$endgroup$
If $ {emptyset} ∈ {emptyset,{emptyset}} $ is true, does it mean this $ emptyset in {{emptyset}} $ true ? If it is not, why it is false?
Also, does $ {{emptyset}}$ mean ${emptyset,{emptyset,{emptyset}}}$ ?
elementary-set-theory
elementary-set-theory
New contributor
New contributor
edited 18 mins ago
user549397
1,2181315
1,2181315
New contributor
asked 57 mins ago
J.SJ.S
62
62
New contributor
New contributor
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
The notation $a in A$ says that among the elements of $A$ there is one element that is exactly equal to $a.$
The notation ${emptyset, {emptyset}}$ describes a set with exactly two elements.
The first element is $emptyset.$ The second element is ${emptyset}.$
Is one of those two elements exactly equal to ${emptyset}$?
The notation ${ {emptyset}}$ describes a set with one element.
That element is ${emptyset}.$
Which element of ${ {emptyset}}$ do you think is exactly equal to $emptyset$?
Hint: there's only one element you have to check.
The notation ${emptyset, {emptyset, {emptyset}}}$ again describes a set with two elements.
One element is $emptyset$ and the other is
${emptyset, {emptyset}}.$
So this is definitely not the same thing as any set that has only one element.
$endgroup$
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
});
}
});
J.S is a new contributor. Be nice, and check out our Code of Conduct.
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%2f3081469%2fis-%25e2%2588%2585-%25e2%2588%2588-%25e2%2588%2585-true%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
$begingroup$
The notation $a in A$ says that among the elements of $A$ there is one element that is exactly equal to $a.$
The notation ${emptyset, {emptyset}}$ describes a set with exactly two elements.
The first element is $emptyset.$ The second element is ${emptyset}.$
Is one of those two elements exactly equal to ${emptyset}$?
The notation ${ {emptyset}}$ describes a set with one element.
That element is ${emptyset}.$
Which element of ${ {emptyset}}$ do you think is exactly equal to $emptyset$?
Hint: there's only one element you have to check.
The notation ${emptyset, {emptyset, {emptyset}}}$ again describes a set with two elements.
One element is $emptyset$ and the other is
${emptyset, {emptyset}}.$
So this is definitely not the same thing as any set that has only one element.
$endgroup$
add a comment |
$begingroup$
The notation $a in A$ says that among the elements of $A$ there is one element that is exactly equal to $a.$
The notation ${emptyset, {emptyset}}$ describes a set with exactly two elements.
The first element is $emptyset.$ The second element is ${emptyset}.$
Is one of those two elements exactly equal to ${emptyset}$?
The notation ${ {emptyset}}$ describes a set with one element.
That element is ${emptyset}.$
Which element of ${ {emptyset}}$ do you think is exactly equal to $emptyset$?
Hint: there's only one element you have to check.
The notation ${emptyset, {emptyset, {emptyset}}}$ again describes a set with two elements.
One element is $emptyset$ and the other is
${emptyset, {emptyset}}.$
So this is definitely not the same thing as any set that has only one element.
$endgroup$
add a comment |
$begingroup$
The notation $a in A$ says that among the elements of $A$ there is one element that is exactly equal to $a.$
The notation ${emptyset, {emptyset}}$ describes a set with exactly two elements.
The first element is $emptyset.$ The second element is ${emptyset}.$
Is one of those two elements exactly equal to ${emptyset}$?
The notation ${ {emptyset}}$ describes a set with one element.
That element is ${emptyset}.$
Which element of ${ {emptyset}}$ do you think is exactly equal to $emptyset$?
Hint: there's only one element you have to check.
The notation ${emptyset, {emptyset, {emptyset}}}$ again describes a set with two elements.
One element is $emptyset$ and the other is
${emptyset, {emptyset}}.$
So this is definitely not the same thing as any set that has only one element.
$endgroup$
The notation $a in A$ says that among the elements of $A$ there is one element that is exactly equal to $a.$
The notation ${emptyset, {emptyset}}$ describes a set with exactly two elements.
The first element is $emptyset.$ The second element is ${emptyset}.$
Is one of those two elements exactly equal to ${emptyset}$?
The notation ${ {emptyset}}$ describes a set with one element.
That element is ${emptyset}.$
Which element of ${ {emptyset}}$ do you think is exactly equal to $emptyset$?
Hint: there's only one element you have to check.
The notation ${emptyset, {emptyset, {emptyset}}}$ again describes a set with two elements.
One element is $emptyset$ and the other is
${emptyset, {emptyset}}.$
So this is definitely not the same thing as any set that has only one element.
answered 39 mins ago
David KDavid K
53.4k341115
53.4k341115
add a comment |
add a comment |
J.S is a new contributor. Be nice, and check out our Code of Conduct.
J.S is a new contributor. Be nice, and check out our Code of Conduct.
J.S is a new contributor. Be nice, and check out our Code of Conduct.
J.S is a new contributor. Be nice, and check out our Code of Conduct.
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%2f3081469%2fis-%25e2%2588%2585-%25e2%2588%2588-%25e2%2588%2585-true%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