Mar
23
answered If $(X,d)$ is a finite metric space , then every ideal of $C(X, \mathbb R)$ is generated by an idempotent ?
Mar
23
comment If $(X,d)$ is a finite metric space , then is every prime ideal of $C(X, \mathbb R)$ maximal?
@martini Notice it says no nonzero nilpotent elements.
Mar
23
revised If $(X,d)$ is a finite metric space , then is every prime ideal of $C(X, \mathbb R)$ maximal?
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Mar
23
answered If $(X,d)$ is a finite metric space , then is every prime ideal of $C(X, \mathbb R)$ maximal?
Mar
23
comment Can “$0^0$” be defined?
Search tip: while 0^0 did not get the dupe at the top of the search results, quoting that string did give me one in the second slot.
Mar
23
comment Can “$0^0$” be defined?
@AlexHalm I believe that's also addressed at the dupe.
Mar
23
comment Can “$0^0$” be defined?
@Surb I linked the most likely dupe.
Mar
23
comment Equivalence of Semisimplicity
@RhysEvans No problem: good luck!
Mar
23
answered Equivalence of Semisimplicity
Mar
23
comment please help me to calculate this question!!! plsss
Click the edit history link to see how I changed your image into readable text. It only took about 10 seconds. This makes your question higher visibility.
Mar
23
revised please help me to calculate this question!!! plsss
made image into readable text
Mar
23
comment please help me to calculate this question!!! plsss
I would like to hear more about what you tried. Also, please consider using titles that aren't malgrammatical cries for help. You'll get a much warmer response if you actually describe what your question is about.
Mar
23
revised Why Can't we Factor Invertible Elements?
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Mar
23
revised Why Can't we Factor Invertible Elements?
added 617 characters in body
Mar
23
answered Why Can't we Factor Invertible Elements?
Mar
22
comment All nilpotent $2\times 2$ matrices
@lhf I guess there is a typo in "all nilpotent matrices subject to ad−bc≠0" because the set is empty. Nilpotent matrices will certainly always have determinant zero... But yeah, the suggestion to simply compute $A^2$ for a square matrix certainly leads to a parametrization.
Mar
22
revised I have to show nullity M is more than or equal to $n/2$.
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Mar
22
comment I have to show one of nullity $A$ or nullity (I-A) is at least $n/2$.
So $B$ has nothing to do with anything? Or is there a typo?
Mar
22
comment Show that if $a \in R$ has more than one left-inverse then it has infinite.
Something at a duplicate linked to the duplicate may also be useful.
Mar
21
comment Quaternion algebra of characteristic 2?
@pval yes, right. At any rate, the group algebra is 8 dimensional while the quaternion algebras are 4 dimensional. And group algebras almost always have a nontrivial ideal :)