Showing why $Bbb Z^-∩Bbb Z^+=∅$ is trueAddition of cardinalitiesProving relation $(x,y)in Bbb RtimesBbb Rmid y = x^2$ is not a transitive relationConfusion about the null (empty) set being contained in other setsProvide a counter example to the claim that "for every set S, if ∅∈P(S) , then ∅∈SProviding counterexamples to the claim: If $|A cap B| < |A|$ then $|A|>|B|$How to show that $bigcup_ninBbb Nleft[0,1-frac 1nright]=[0,1)$?Proving True or False, Set QuestionHow do you prove the statement: $P(A cap B)=P(A) cap P(B)$If $A^X$ is equipotent to $B^X$ does it imply that A is equipotent to B?A Countable Well-ordered (w.r.to usual order) subset of $BbbR$ which is not of same order type with a subset of $BbbN$
Memorizing the Keyboard
Do I have a twin with permutated remainders?
Why does Kotter return in Welcome Back Kotter?
Why do bosons tend to occupy the same state?
If human space travel is limited by the G force vulnerability, is there a way to counter G forces?
Is it canonical bit space?
Is the Joker left-handed?
Is it possible to create light that imparts a greater proportion of its energy as momentum rather than heat?
Theorems that impeded progress
Why is the 'in' operator throwing an error with a string literal instead of logging false?
Fully-Firstable Anagram Sets
Why is consensus so controversial in Britain?
Why doesn't using multiple commands with a || or && conditional work?
How can I make my BBEG immortal short of making them a Lich or Vampire?
I'm flying to France today and my passport expires in less than 2 months
Why can't we play rap on piano?
Forgetting the musical notes while performing in concert
What to put in ESTA if staying in US for a few days before going on to Canada
I Accidentally Deleted a Stock Terminal Theme
What is going on with Captain Marvel's blood colour?
What is the intuition behind short exact sequences of groups; in particular, what is the intuition behind group extensions?
Why are electrically insulating heatsinks so rare? Is it just cost?
A reference to a well-known characterization of scattered compact spaces
Can a rocket refuel on Mars from water?
Showing why $Bbb Z^-∩Bbb Z^+=∅$ is true
Addition of cardinalitiesProving relation $(x,y)in Bbb RtimesBbb Rmid y = x^2$ is not a transitive relationConfusion about the null (empty) set being contained in other setsProvide a counter example to the claim that "for every set S, if ∅∈P(S) , then ∅∈SProviding counterexamples to the claim: If $|A cap B| < |A|$ then $|A|>|B|$How to show that $bigcup_ninBbb Nleft[0,1-frac 1nright]=[0,1)$?Proving True or False, Set QuestionHow do you prove the statement: $P(A cap B)=P(A) cap P(B)$If $A^X$ is equipotent to $B^X$ does it imply that A is equipotent to B?A Countable Well-ordered (w.r.to usual order) subset of $BbbR$ which is not of same order type with a subset of $BbbN$
$begingroup$
My Problem: Is this statement true or false? Give a reason. If false a counter example is adequate.
$$Bbb Z^-∩Bbb Z^+=∅$$
I'm more so after the reasoning as I don't know how to word it. I know the statement is true.
elementary-set-theory
$endgroup$
add a comment |
$begingroup$
My Problem: Is this statement true or false? Give a reason. If false a counter example is adequate.
$$Bbb Z^-∩Bbb Z^+=∅$$
I'm more so after the reasoning as I don't know how to word it. I know the statement is true.
elementary-set-theory
$endgroup$
add a comment |
$begingroup$
My Problem: Is this statement true or false? Give a reason. If false a counter example is adequate.
$$Bbb Z^-∩Bbb Z^+=∅$$
I'm more so after the reasoning as I don't know how to word it. I know the statement is true.
elementary-set-theory
$endgroup$
My Problem: Is this statement true or false? Give a reason. If false a counter example is adequate.
$$Bbb Z^-∩Bbb Z^+=∅$$
I'm more so after the reasoning as I don't know how to word it. I know the statement is true.
elementary-set-theory
elementary-set-theory
edited Mar 30 at 0:15
Andrés E. Caicedo
65.9k8160252
65.9k8160252
asked Mar 29 at 3:44
JMWJMW
62
62
add a comment |
add a comment |
2 Answers
2
active
oldest
votes
$begingroup$
I don't really think there is any particularly "elegant" logic needed - simply that they don't share a common element. It basically amounts to "there is no integer which is both positive and negative."
I guess if you want to argue it in a somewhat formal way, you can say that, for all $n in Bbb Z^-$, $n < 0$, and for all $m in Bbb Z^+$, $m > 0$. If there exists an element $k$ in the intersection of the two, this means $k<0$, but also $k>0$, which is simply not possible.
$endgroup$
add a comment |
$begingroup$
An intersection of two sets is the set of elements that are in both sets.
$mathbb Z^+$ is the set of integers that are positive and $mathbb Z^-$ is the set of integer that are negative. So $mathbb Z^+ cap mathbb Z^+$ are the set of integers that are both positive and negative.
To be negative is to be less than $0$ and to be positive is to be bigger than $0$. A fundamental principal of real numbers is that for any $a,b$ either $a < b; a=b$ or $a > b$-- exactly one and only one of those is true. So an integer being both greater than and less than $0$ is impossible.
$endgroup$
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%2f3166721%2fshowing-why-bbb-z-%25e2%2588%25a9-bbb-z-%25e2%2588%2585-is-true%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
$begingroup$
I don't really think there is any particularly "elegant" logic needed - simply that they don't share a common element. It basically amounts to "there is no integer which is both positive and negative."
I guess if you want to argue it in a somewhat formal way, you can say that, for all $n in Bbb Z^-$, $n < 0$, and for all $m in Bbb Z^+$, $m > 0$. If there exists an element $k$ in the intersection of the two, this means $k<0$, but also $k>0$, which is simply not possible.
$endgroup$
add a comment |
$begingroup$
I don't really think there is any particularly "elegant" logic needed - simply that they don't share a common element. It basically amounts to "there is no integer which is both positive and negative."
I guess if you want to argue it in a somewhat formal way, you can say that, for all $n in Bbb Z^-$, $n < 0$, and for all $m in Bbb Z^+$, $m > 0$. If there exists an element $k$ in the intersection of the two, this means $k<0$, but also $k>0$, which is simply not possible.
$endgroup$
add a comment |
$begingroup$
I don't really think there is any particularly "elegant" logic needed - simply that they don't share a common element. It basically amounts to "there is no integer which is both positive and negative."
I guess if you want to argue it in a somewhat formal way, you can say that, for all $n in Bbb Z^-$, $n < 0$, and for all $m in Bbb Z^+$, $m > 0$. If there exists an element $k$ in the intersection of the two, this means $k<0$, but also $k>0$, which is simply not possible.
$endgroup$
I don't really think there is any particularly "elegant" logic needed - simply that they don't share a common element. It basically amounts to "there is no integer which is both positive and negative."
I guess if you want to argue it in a somewhat formal way, you can say that, for all $n in Bbb Z^-$, $n < 0$, and for all $m in Bbb Z^+$, $m > 0$. If there exists an element $k$ in the intersection of the two, this means $k<0$, but also $k>0$, which is simply not possible.
answered Mar 29 at 3:48
Eevee TrainerEevee Trainer
9,70031740
9,70031740
add a comment |
add a comment |
$begingroup$
An intersection of two sets is the set of elements that are in both sets.
$mathbb Z^+$ is the set of integers that are positive and $mathbb Z^-$ is the set of integer that are negative. So $mathbb Z^+ cap mathbb Z^+$ are the set of integers that are both positive and negative.
To be negative is to be less than $0$ and to be positive is to be bigger than $0$. A fundamental principal of real numbers is that for any $a,b$ either $a < b; a=b$ or $a > b$-- exactly one and only one of those is true. So an integer being both greater than and less than $0$ is impossible.
$endgroup$
add a comment |
$begingroup$
An intersection of two sets is the set of elements that are in both sets.
$mathbb Z^+$ is the set of integers that are positive and $mathbb Z^-$ is the set of integer that are negative. So $mathbb Z^+ cap mathbb Z^+$ are the set of integers that are both positive and negative.
To be negative is to be less than $0$ and to be positive is to be bigger than $0$. A fundamental principal of real numbers is that for any $a,b$ either $a < b; a=b$ or $a > b$-- exactly one and only one of those is true. So an integer being both greater than and less than $0$ is impossible.
$endgroup$
add a comment |
$begingroup$
An intersection of two sets is the set of elements that are in both sets.
$mathbb Z^+$ is the set of integers that are positive and $mathbb Z^-$ is the set of integer that are negative. So $mathbb Z^+ cap mathbb Z^+$ are the set of integers that are both positive and negative.
To be negative is to be less than $0$ and to be positive is to be bigger than $0$. A fundamental principal of real numbers is that for any $a,b$ either $a < b; a=b$ or $a > b$-- exactly one and only one of those is true. So an integer being both greater than and less than $0$ is impossible.
$endgroup$
An intersection of two sets is the set of elements that are in both sets.
$mathbb Z^+$ is the set of integers that are positive and $mathbb Z^-$ is the set of integer that are negative. So $mathbb Z^+ cap mathbb Z^+$ are the set of integers that are both positive and negative.
To be negative is to be less than $0$ and to be positive is to be bigger than $0$. A fundamental principal of real numbers is that for any $a,b$ either $a < b; a=b$ or $a > b$-- exactly one and only one of those is true. So an integer being both greater than and less than $0$ is impossible.
answered Mar 30 at 0:48
fleabloodfleablood
73.8k22891
73.8k22891
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%2f3166721%2fshowing-why-bbb-z-%25e2%2588%25a9-bbb-z-%25e2%2588%2585-is-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