Proving 2 languages are equal.











up vote
0
down vote

favorite












I am quite new to Discrete Math and having lots of troubles solving the problems in it.



Currently, I am struggling with a problem:



Prove by induction that if $A$ and $B$ are regular expressions over one-letter alphabet and if $n$ is any natural, prove that languages $(AB)^n$ and $A^nB^n$ are equal.



Thanks










share|cite|improve this question









New contributor




Alan Bui is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.




















  • Have you tried some simple example? If the alphabet is ${1}$, $A=11$ and $B=1$, what do you get?
    – Fabio Somenzi
    yesterday










  • Sorry to say this but I am pretty much lost and do not know where to start my thing. I need some examples so I can follow it.
    – Alan Bui
    yesterday










  • If $A$ and $B$ are as above and $n=2$, $(AB)^n = (111)^2 = 111111$ and $A^nB^n = (11)^2(1)^2 = 111111$.
    – Fabio Somenzi
    yesterday










  • @FabioSomenzi can you please do an example with $A=a$ and $B=b$ where $a neq b$ or $a$ and $b$ are not concats of each other?
    – keoxkeox
    23 hours ago












  • @keoxkeox The alphabet is supposed to have only one letter; otherwise the claim is obviously wrong.
    – Fabio Somenzi
    23 hours ago















up vote
0
down vote

favorite












I am quite new to Discrete Math and having lots of troubles solving the problems in it.



Currently, I am struggling with a problem:



Prove by induction that if $A$ and $B$ are regular expressions over one-letter alphabet and if $n$ is any natural, prove that languages $(AB)^n$ and $A^nB^n$ are equal.



Thanks










share|cite|improve this question









New contributor




Alan Bui is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.




















  • Have you tried some simple example? If the alphabet is ${1}$, $A=11$ and $B=1$, what do you get?
    – Fabio Somenzi
    yesterday










  • Sorry to say this but I am pretty much lost and do not know where to start my thing. I need some examples so I can follow it.
    – Alan Bui
    yesterday










  • If $A$ and $B$ are as above and $n=2$, $(AB)^n = (111)^2 = 111111$ and $A^nB^n = (11)^2(1)^2 = 111111$.
    – Fabio Somenzi
    yesterday










  • @FabioSomenzi can you please do an example with $A=a$ and $B=b$ where $a neq b$ or $a$ and $b$ are not concats of each other?
    – keoxkeox
    23 hours ago












  • @keoxkeox The alphabet is supposed to have only one letter; otherwise the claim is obviously wrong.
    – Fabio Somenzi
    23 hours ago













up vote
0
down vote

favorite









up vote
0
down vote

favorite











I am quite new to Discrete Math and having lots of troubles solving the problems in it.



Currently, I am struggling with a problem:



Prove by induction that if $A$ and $B$ are regular expressions over one-letter alphabet and if $n$ is any natural, prove that languages $(AB)^n$ and $A^nB^n$ are equal.



Thanks










share|cite|improve this question









New contributor




Alan Bui is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











I am quite new to Discrete Math and having lots of troubles solving the problems in it.



Currently, I am struggling with a problem:



Prove by induction that if $A$ and $B$ are regular expressions over one-letter alphabet and if $n$ is any natural, prove that languages $(AB)^n$ and $A^nB^n$ are equal.



Thanks







discrete-mathematics regular-expressions






share|cite|improve this question









New contributor




Alan Bui is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











share|cite|improve this question









New contributor




Alan Bui is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









share|cite|improve this question




share|cite|improve this question








edited yesterday





















New contributor




Alan Bui is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









asked yesterday









Alan Bui

113




113




New contributor




Alan Bui is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.





New contributor





Alan Bui is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.






Alan Bui is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.












  • Have you tried some simple example? If the alphabet is ${1}$, $A=11$ and $B=1$, what do you get?
    – Fabio Somenzi
    yesterday










  • Sorry to say this but I am pretty much lost and do not know where to start my thing. I need some examples so I can follow it.
    – Alan Bui
    yesterday










  • If $A$ and $B$ are as above and $n=2$, $(AB)^n = (111)^2 = 111111$ and $A^nB^n = (11)^2(1)^2 = 111111$.
    – Fabio Somenzi
    yesterday










  • @FabioSomenzi can you please do an example with $A=a$ and $B=b$ where $a neq b$ or $a$ and $b$ are not concats of each other?
    – keoxkeox
    23 hours ago












  • @keoxkeox The alphabet is supposed to have only one letter; otherwise the claim is obviously wrong.
    – Fabio Somenzi
    23 hours ago


















  • Have you tried some simple example? If the alphabet is ${1}$, $A=11$ and $B=1$, what do you get?
    – Fabio Somenzi
    yesterday










  • Sorry to say this but I am pretty much lost and do not know where to start my thing. I need some examples so I can follow it.
    – Alan Bui
    yesterday










  • If $A$ and $B$ are as above and $n=2$, $(AB)^n = (111)^2 = 111111$ and $A^nB^n = (11)^2(1)^2 = 111111$.
    – Fabio Somenzi
    yesterday










  • @FabioSomenzi can you please do an example with $A=a$ and $B=b$ where $a neq b$ or $a$ and $b$ are not concats of each other?
    – keoxkeox
    23 hours ago












  • @keoxkeox The alphabet is supposed to have only one letter; otherwise the claim is obviously wrong.
    – Fabio Somenzi
    23 hours ago
















Have you tried some simple example? If the alphabet is ${1}$, $A=11$ and $B=1$, what do you get?
– Fabio Somenzi
yesterday




Have you tried some simple example? If the alphabet is ${1}$, $A=11$ and $B=1$, what do you get?
– Fabio Somenzi
yesterday












Sorry to say this but I am pretty much lost and do not know where to start my thing. I need some examples so I can follow it.
– Alan Bui
yesterday




Sorry to say this but I am pretty much lost and do not know where to start my thing. I need some examples so I can follow it.
– Alan Bui
yesterday












If $A$ and $B$ are as above and $n=2$, $(AB)^n = (111)^2 = 111111$ and $A^nB^n = (11)^2(1)^2 = 111111$.
– Fabio Somenzi
yesterday




If $A$ and $B$ are as above and $n=2$, $(AB)^n = (111)^2 = 111111$ and $A^nB^n = (11)^2(1)^2 = 111111$.
– Fabio Somenzi
yesterday












@FabioSomenzi can you please do an example with $A=a$ and $B=b$ where $a neq b$ or $a$ and $b$ are not concats of each other?
– keoxkeox
23 hours ago






@FabioSomenzi can you please do an example with $A=a$ and $B=b$ where $a neq b$ or $a$ and $b$ are not concats of each other?
– keoxkeox
23 hours ago














@keoxkeox The alphabet is supposed to have only one letter; otherwise the claim is obviously wrong.
– Fabio Somenzi
23 hours ago




@keoxkeox The alphabet is supposed to have only one letter; otherwise the claim is obviously wrong.
– Fabio Somenzi
23 hours ago















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',
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
});


}
});






Alan Bui is a new contributor. Be nice, and check out our Code of Conduct.










 

draft saved


draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3004547%2fproving-2-languages-are-equal%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown






























active

oldest

votes













active

oldest

votes









active

oldest

votes






active

oldest

votes








Alan Bui is a new contributor. Be nice, and check out our Code of Conduct.










 

draft saved


draft discarded


















Alan Bui is a new contributor. Be nice, and check out our Code of Conduct.













Alan Bui is a new contributor. Be nice, and check out our Code of Conduct.












Alan Bui is a new contributor. Be nice, and check out our Code of Conduct.















 


draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3004547%2fproving-2-languages-are-equal%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

Can a sorcerer learn a 5th-level spell early by creating spell slots using the Font of Magic feature?

Does disintegrating a polymorphed enemy still kill it after the 2018 errata?

A Topological Invariant for $pi_3(U(n))$