Can I say dim range $T = $ dim null $S$ + range $S$ if $S in mathcalL(V,W)$, and $T in mathcalL(U,V)$?If two vector spaces $V$ and $W$ are isomorphic and $V$ is F-D then $W$ is F-D. Furthermore, $textdim V = textdim W$.Dimension of Range and Null Space of Composition of Two Linear Maps$textnull,T^ksubsetneqtextnull,T^k+1$ and $textrange,T^ksupsetneqtextrange,T^k+1$ for all $kinmathbbN$If $T in mathcalL(V)$ is diagonalizable and V is infinite dimensional, then $V = null (T) oplus range (T)$.If $operatornamerangeT' = operatornamespan(varphi)$, then $operatornamenull T = operatornamenull varphi$Does $textnull T^m = textnull T^m+1$ if and only if $textrange T^m = textrange T^m+1$ hold in infinite dimensional vector spaces?An intuitive argument demonstrating $dimoperatornamerangeSTleqmindimoperatornamerangeS,dimoperatornamerangeT$Proving that $dimoperatornamenullSTleqdimoperatornamenullT+dimoperatornamenullS$.How to prove that $textnull ;T_1 subset textnull ;T_2$ implies $textdim(range; T_1) geq textdim(range T_2)$?A map to a larger dimensional space is not surjective

What ability score modifier does a javelin's damage use?

Giving a career talk in my old university, how prominently should I tell students my salary?

Would an aboleth's Phantasmal Force lair action be affected by Counterspell, Dispel Magic, and/or Slow?

Does an unused member variable take up memory?

Which situations would cause a company to ground or recall a aircraft series?

What do *foreign films* mean for an American?

Street obstacles in New Zealand

Rationale to prefer local variables over instance variables?

What's the 'present simple' form of the word "нашла́" in 3rd person singular female?

What is the generally accepted pronunciation of “topoi”?

What do you call someone who likes to pick fights?

Why do we say ‘pairwise disjoint’, rather than ‘disjoint’?

Should I take out a loan for a friend to invest on my behalf?

Possible to detect presence of nuclear bomb?

Doubts in understanding some concepts of potential energy

In the late 1940’s to early 1950’s what technology was available that could melt a LOT of ice?

After `ssh` without `-X` to a machine, is it possible to change `$DISPLAY` to make it work like `ssh -X`?

Do cubics always have one real root?

What would be the most expensive material to an intergalactic society?

PTIJ: Why does only a Shor Tam ask at the Seder, and not a Shor Mu'ad?

Are there historical instances of the capital of a colonising country being temporarily or permanently shifted to one of its colonies?

Is a piano played in the same way as a harmonium?

Does "Until when" sound natural for native speakers?

Is it possible that a question has only two answers?



Can I say dim range $T = $ dim null $S$ + range $S$ if $S in mathcalL(V,W)$, and $T in mathcalL(U,V)$?


If two vector spaces $V$ and $W$ are isomorphic and $V$ is F-D then $W$ is F-D. Furthermore, $textdim V = textdim W$.Dimension of Range and Null Space of Composition of Two Linear Maps$textnull,T^ksubsetneqtextnull,T^k+1$ and $textrange,T^ksupsetneqtextrange,T^k+1$ for all $kinmathbbN$If $T in mathcalL(V)$ is diagonalizable and V is infinite dimensional, then $V = null (T) oplus range (T)$.If $operatornamerangeT' = operatornamespan(varphi)$, then $operatornamenull T = operatornamenull varphi$Does $textnull T^m = textnull T^m+1$ if and only if $textrange T^m = textrange T^m+1$ hold in infinite dimensional vector spaces?An intuitive argument demonstrating $dimoperatornamerangeSTleqmindimoperatornamerangeS,dimoperatornamerangeT$Proving that $dimoperatornamenullSTleqdimoperatornamenullT+dimoperatornamenullS$.How to prove that $textnull ;T_1 subset textnull ;T_2$ implies $textdim(range; T_1) geq textdim(range T_2)$?A map to a larger dimensional space is not surjective













1












$begingroup$


Can I say dim range $T = $ dim null $S$ + range $S$ if $S in mathcalL(V,W)$, and $T in mathcalL(U,V)$?



The reason I asked this is because I am doing Q22 of section 3.B on Linear Algebra Done Right.




Suppose $U$ and $V$ are finite-dimensional vector spaces and $S in mathcalL(V,W)$, and $T in mathcalL(U,V)$. Prove that $$textdim null ST leq textdim null S + textdim null T$$




My failed trail is as follow:



dim range $T = $ dim null $S$ + dim range $S$ (from S)



dim $U$ = dim null $T$ + dim range $T$ (from T)



dim $U$ = dim null $ST$ + dim range $ST$ (from $ST in mathcalL(U,W)$)



then



dim null $T$ + dim range $T$ = dim null $ST$ + dim range $ST$



dim null $T$ + dim null $S$ + dim range $S$ = dim null $ST$ + dim range $ST$



dim null $ST$ = dim null $T$ + dim null $S$ + dim range $S$ - dim range $ST$



The trial seems not working. Maybe range $T = $ dim null $S$ + dim range $S$ is wrong in the first place.










share|cite|improve this question











$endgroup$











  • $begingroup$
    Your first step is wrong indeed. There is nothing which says that $T$ should depend on $S$. Moreover, your notation is a bit weird in that statement. You say the range (a set) of $T$ is a number plus another set. You can define adding numbers to sets but I am not sure what your thought was?
    $endgroup$
    – Stan Tendijck
    yesterday










  • $begingroup$
    If ai were you I would more argue in the trend: given a 'vector' in the nullspace of $ST$, show that you can relate this to a vector in the nullspace of $S$ or $T$
    $endgroup$
    – Stan Tendijck
    yesterday










  • $begingroup$
    @StanTendijck The notation was a typo. My thought was since $ST(u)$ can be written as $S(T(u))$, I thought the range of $T$ is the domain of $S$.
    $endgroup$
    – JOHN
    yesterday










  • $begingroup$
    If $T=0$, then $dim ,textRan, T=0$.
    $endgroup$
    – Yiorgos S. Smyrlis
    yesterday











  • $begingroup$
    @John ok so what you need for it to work is that the range of $T$ is a subset of the domain of $S$. Per definition this is true since $T$s domain is part of $V$ which is exactly the domain of $S$ per definition.
    $endgroup$
    – Stan Tendijck
    yesterday















1












$begingroup$


Can I say dim range $T = $ dim null $S$ + range $S$ if $S in mathcalL(V,W)$, and $T in mathcalL(U,V)$?



The reason I asked this is because I am doing Q22 of section 3.B on Linear Algebra Done Right.




Suppose $U$ and $V$ are finite-dimensional vector spaces and $S in mathcalL(V,W)$, and $T in mathcalL(U,V)$. Prove that $$textdim null ST leq textdim null S + textdim null T$$




My failed trail is as follow:



dim range $T = $ dim null $S$ + dim range $S$ (from S)



dim $U$ = dim null $T$ + dim range $T$ (from T)



dim $U$ = dim null $ST$ + dim range $ST$ (from $ST in mathcalL(U,W)$)



then



dim null $T$ + dim range $T$ = dim null $ST$ + dim range $ST$



dim null $T$ + dim null $S$ + dim range $S$ = dim null $ST$ + dim range $ST$



dim null $ST$ = dim null $T$ + dim null $S$ + dim range $S$ - dim range $ST$



The trial seems not working. Maybe range $T = $ dim null $S$ + dim range $S$ is wrong in the first place.










share|cite|improve this question











$endgroup$











  • $begingroup$
    Your first step is wrong indeed. There is nothing which says that $T$ should depend on $S$. Moreover, your notation is a bit weird in that statement. You say the range (a set) of $T$ is a number plus another set. You can define adding numbers to sets but I am not sure what your thought was?
    $endgroup$
    – Stan Tendijck
    yesterday










  • $begingroup$
    If ai were you I would more argue in the trend: given a 'vector' in the nullspace of $ST$, show that you can relate this to a vector in the nullspace of $S$ or $T$
    $endgroup$
    – Stan Tendijck
    yesterday










  • $begingroup$
    @StanTendijck The notation was a typo. My thought was since $ST(u)$ can be written as $S(T(u))$, I thought the range of $T$ is the domain of $S$.
    $endgroup$
    – JOHN
    yesterday










  • $begingroup$
    If $T=0$, then $dim ,textRan, T=0$.
    $endgroup$
    – Yiorgos S. Smyrlis
    yesterday











  • $begingroup$
    @John ok so what you need for it to work is that the range of $T$ is a subset of the domain of $S$. Per definition this is true since $T$s domain is part of $V$ which is exactly the domain of $S$ per definition.
    $endgroup$
    – Stan Tendijck
    yesterday













1












1








1





$begingroup$


Can I say dim range $T = $ dim null $S$ + range $S$ if $S in mathcalL(V,W)$, and $T in mathcalL(U,V)$?



The reason I asked this is because I am doing Q22 of section 3.B on Linear Algebra Done Right.




Suppose $U$ and $V$ are finite-dimensional vector spaces and $S in mathcalL(V,W)$, and $T in mathcalL(U,V)$. Prove that $$textdim null ST leq textdim null S + textdim null T$$




My failed trail is as follow:



dim range $T = $ dim null $S$ + dim range $S$ (from S)



dim $U$ = dim null $T$ + dim range $T$ (from T)



dim $U$ = dim null $ST$ + dim range $ST$ (from $ST in mathcalL(U,W)$)



then



dim null $T$ + dim range $T$ = dim null $ST$ + dim range $ST$



dim null $T$ + dim null $S$ + dim range $S$ = dim null $ST$ + dim range $ST$



dim null $ST$ = dim null $T$ + dim null $S$ + dim range $S$ - dim range $ST$



The trial seems not working. Maybe range $T = $ dim null $S$ + dim range $S$ is wrong in the first place.










share|cite|improve this question











$endgroup$




Can I say dim range $T = $ dim null $S$ + range $S$ if $S in mathcalL(V,W)$, and $T in mathcalL(U,V)$?



The reason I asked this is because I am doing Q22 of section 3.B on Linear Algebra Done Right.




Suppose $U$ and $V$ are finite-dimensional vector spaces and $S in mathcalL(V,W)$, and $T in mathcalL(U,V)$. Prove that $$textdim null ST leq textdim null S + textdim null T$$




My failed trail is as follow:



dim range $T = $ dim null $S$ + dim range $S$ (from S)



dim $U$ = dim null $T$ + dim range $T$ (from T)



dim $U$ = dim null $ST$ + dim range $ST$ (from $ST in mathcalL(U,W)$)



then



dim null $T$ + dim range $T$ = dim null $ST$ + dim range $ST$



dim null $T$ + dim null $S$ + dim range $S$ = dim null $ST$ + dim range $ST$



dim null $ST$ = dim null $T$ + dim null $S$ + dim range $S$ - dim range $ST$



The trial seems not working. Maybe range $T = $ dim null $S$ + dim range $S$ is wrong in the first place.







linear-algebra linear-transformations






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited yesterday







JOHN

















asked yesterday









JOHN JOHN

4209




4209











  • $begingroup$
    Your first step is wrong indeed. There is nothing which says that $T$ should depend on $S$. Moreover, your notation is a bit weird in that statement. You say the range (a set) of $T$ is a number plus another set. You can define adding numbers to sets but I am not sure what your thought was?
    $endgroup$
    – Stan Tendijck
    yesterday










  • $begingroup$
    If ai were you I would more argue in the trend: given a 'vector' in the nullspace of $ST$, show that you can relate this to a vector in the nullspace of $S$ or $T$
    $endgroup$
    – Stan Tendijck
    yesterday










  • $begingroup$
    @StanTendijck The notation was a typo. My thought was since $ST(u)$ can be written as $S(T(u))$, I thought the range of $T$ is the domain of $S$.
    $endgroup$
    – JOHN
    yesterday










  • $begingroup$
    If $T=0$, then $dim ,textRan, T=0$.
    $endgroup$
    – Yiorgos S. Smyrlis
    yesterday











  • $begingroup$
    @John ok so what you need for it to work is that the range of $T$ is a subset of the domain of $S$. Per definition this is true since $T$s domain is part of $V$ which is exactly the domain of $S$ per definition.
    $endgroup$
    – Stan Tendijck
    yesterday
















  • $begingroup$
    Your first step is wrong indeed. There is nothing which says that $T$ should depend on $S$. Moreover, your notation is a bit weird in that statement. You say the range (a set) of $T$ is a number plus another set. You can define adding numbers to sets but I am not sure what your thought was?
    $endgroup$
    – Stan Tendijck
    yesterday










  • $begingroup$
    If ai were you I would more argue in the trend: given a 'vector' in the nullspace of $ST$, show that you can relate this to a vector in the nullspace of $S$ or $T$
    $endgroup$
    – Stan Tendijck
    yesterday










  • $begingroup$
    @StanTendijck The notation was a typo. My thought was since $ST(u)$ can be written as $S(T(u))$, I thought the range of $T$ is the domain of $S$.
    $endgroup$
    – JOHN
    yesterday










  • $begingroup$
    If $T=0$, then $dim ,textRan, T=0$.
    $endgroup$
    – Yiorgos S. Smyrlis
    yesterday











  • $begingroup$
    @John ok so what you need for it to work is that the range of $T$ is a subset of the domain of $S$. Per definition this is true since $T$s domain is part of $V$ which is exactly the domain of $S$ per definition.
    $endgroup$
    – Stan Tendijck
    yesterday















$begingroup$
Your first step is wrong indeed. There is nothing which says that $T$ should depend on $S$. Moreover, your notation is a bit weird in that statement. You say the range (a set) of $T$ is a number plus another set. You can define adding numbers to sets but I am not sure what your thought was?
$endgroup$
– Stan Tendijck
yesterday




$begingroup$
Your first step is wrong indeed. There is nothing which says that $T$ should depend on $S$. Moreover, your notation is a bit weird in that statement. You say the range (a set) of $T$ is a number plus another set. You can define adding numbers to sets but I am not sure what your thought was?
$endgroup$
– Stan Tendijck
yesterday












$begingroup$
If ai were you I would more argue in the trend: given a 'vector' in the nullspace of $ST$, show that you can relate this to a vector in the nullspace of $S$ or $T$
$endgroup$
– Stan Tendijck
yesterday




$begingroup$
If ai were you I would more argue in the trend: given a 'vector' in the nullspace of $ST$, show that you can relate this to a vector in the nullspace of $S$ or $T$
$endgroup$
– Stan Tendijck
yesterday












$begingroup$
@StanTendijck The notation was a typo. My thought was since $ST(u)$ can be written as $S(T(u))$, I thought the range of $T$ is the domain of $S$.
$endgroup$
– JOHN
yesterday




$begingroup$
@StanTendijck The notation was a typo. My thought was since $ST(u)$ can be written as $S(T(u))$, I thought the range of $T$ is the domain of $S$.
$endgroup$
– JOHN
yesterday












$begingroup$
If $T=0$, then $dim ,textRan, T=0$.
$endgroup$
– Yiorgos S. Smyrlis
yesterday





$begingroup$
If $T=0$, then $dim ,textRan, T=0$.
$endgroup$
– Yiorgos S. Smyrlis
yesterday













$begingroup$
@John ok so what you need for it to work is that the range of $T$ is a subset of the domain of $S$. Per definition this is true since $T$s domain is part of $V$ which is exactly the domain of $S$ per definition.
$endgroup$
– Stan Tendijck
yesterday




$begingroup$
@John ok so what you need for it to work is that the range of $T$ is a subset of the domain of $S$. Per definition this is true since $T$s domain is part of $V$ which is exactly the domain of $S$ per definition.
$endgroup$
– Stan Tendijck
yesterday










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%2f3140985%2fcan-i-say-dim-range-t-dim-null-s-range-s-if-s-in-mathcallv-w%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%2f3140985%2fcan-i-say-dim-range-t-dim-null-s-range-s-if-s-in-mathcallv-w%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

Lowndes Grove History Architecture References Navigation menu32°48′6″N 79°57′58″W / 32.80167°N 79.96611°W / 32.80167; -79.9661132°48′6″N 79°57′58″W / 32.80167°N 79.96611°W / 32.80167; -79.9661178002500"National Register Information System"Historic houses of South Carolina"Lowndes Grove""+32° 48' 6.00", −79° 57' 58.00""Lowndes Grove, Charleston County (260 St. Margaret St., Charleston)""Lowndes Grove"The Charleston ExpositionIt Happened in South Carolina"Lowndes Grove (House), Saint Margaret Street & Sixth Avenue, Charleston, Charleston County, SC(Photographs)"Plantations of the Carolina Low Countrye

random experiment with two different functions on unit interval Announcing the arrival of Valued Associate #679: Cesar Manara Planned maintenance scheduled April 23, 2019 at 00:00UTC (8:00pm US/Eastern)Random variable and probability space notionsRandom Walk with EdgesFinding functions where the increase over a random interval is Poisson distributedNumber of days until dayCan an observed event in fact be of zero probability?Unit random processmodels of coins and uniform distributionHow to get the number of successes given $n$ trials , probability $P$ and a random variable $X$Absorbing Markov chain in a computer. Is “almost every” turned into always convergence in computer executions?Stopped random walk is not uniformly integrable

How should I support this large drywall patch? Planned maintenance scheduled April 23, 2019 at 00:00UTC (8:00pm US/Eastern) Announcing the arrival of Valued Associate #679: Cesar Manara Unicorn Meta Zoo #1: Why another podcast?How do I cover large gaps in drywall?How do I keep drywall around a patch from crumbling?Can I glue a second layer of drywall?How to patch long strip on drywall?Large drywall patch: how to avoid bulging seams?Drywall Mesh Patch vs. Bulge? To remove or not to remove?How to fix this drywall job?Prep drywall before backsplashWhat's the best way to fix this horrible drywall patch job?Drywall patching using 3M Patch Plus Primer