Alyosha
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 Nov15 asked Is there a general way to prove series and products are modular? Nov9 answered How many subgroups or order 8 an abelian Group of order 72 can have Oct26 comment Extension field of finite degree Do you mean finite? Oct25 comment condition for homeomorphism Are $A,B$ open sets? Oct24 comment Path connected iff the action of $\pi_1(Y,y)$ on $p^{-1}(y)$ is transitive. If I have been unclear, please ask for clarification or rephrasing of my answer. Oct24 answered Path connected iff the action of $\pi_1(Y,y)$ on $p^{-1}(y)$ is transitive. Oct24 comment Prove that the number of automorphisms in $\mathbb Q[\alpha]$ equals $1$ $(|Aut\mathbb Q[\alpha]|)=1$ @Walterr if $\alpha, \beta, \gamma$ are the roots, then $f(a_1 \alpha+a_2 \alpha^2 +b_1 \beta +b_2 \beta^2 +c_1 \gamma +c_2 \gamma^2+d)=a_1 f(\alpha)+a_2 f(\alpha)^2+b_1 f(\beta)+b_2 f(\beta)^2 +c_1 f(\gamma)+c_2 f(\gamma)^2+d.$ Thus $f(l)$ for any $l \in L$ is determined by the action of $f$ on the three roots. Oct24 comment Prove that the number of automorphisms in $\mathbb Q[\alpha]$ equals $1$ $(|Aut\mathbb Q[\alpha]|)=1$ @Walterr I mean that one of $f(\alpha)=\alpha, f(\alpha)=\omega \alpha, f(\alpha)=\omega^2 \alpha$ will occur, and for each of these options you have $2$ choices as to what $f(\alpha \omega)$ is (which, along with $f(\alpha)$, determines $f(\omega^2 \alpha)$). Oct24 answered Prove that the number of automorphisms in $\mathbb Q[\alpha]$ equals $1$ $(|Aut\mathbb Q[\alpha]|)=1$ Oct23 comment How to visualise Bollobas' 1965 theorem? I have crossposted to MO. Oct23 answered Why in this sense this homomorphism is injective? Oct21 comment So why isn't $\Bbb R^n = \oplus _{n = 1}^{m}\Bbb R^n$ Decomposed uniquely. Oct20 revised How to visualise Bollobas' 1965 theorem? added 444 characters in body Oct20 comment $|A\times B|= \text{max}(|A|,|B|)$ for infinite sets I will accept an answer when I've read into this a little more. Oct20 revised How to visualise Bollobas' 1965 theorem? edited body Oct20 revised How to visualise Bollobas' 1965 theorem? edited title Oct20 asked How to visualise Bollobas' 1965 theorem? Oct18 comment $|A\times B|= \text{max}(|A|,|B|)$ for infinite sets How would you apply Zorn here? The obvious partial ordering by inclusion doesn't work directly. Oct18 comment $|A\times B|= \text{max}(|A|,|B|)$ for infinite sets @AsafKaragila I searched for a while and found similar questions that seemed similar but simply cited the result. Oct18 asked $|A\times B|= \text{max}(|A|,|B|)$ for infinite sets