# catamite

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bio website reddit.com/r/… location meatspace age member for 1 year, 11 months seen 1 hour ago profile views 1,026

when someone smiles at me, all I see is an ape bearing its teethe

# 573 Actions

 Jul2 comment Let $Y$ be an ordered set in the order topology with $f,g:X\rightarrow Y$ continuous, show that $\{x:f(x)\leq g(x)\}$ is closed in $X$ Ok after going over this all yesterday I'm pretty sure my book doesn't have (a) and (b) switched. To prove your hint requires the pasting lemma which requires that my set $A$ be closed. So as far as I can tell part (a) is necessary for part (b) and not the other way around. Jul2 comment Let $Y$ be an ordered set in the order topology with $f,g:X\rightarrow Y$ continuous, show that $\{x:f(x)\leq g(x)\}$ is closed in $X$ On line two of your proof I think you meant "in $Y$" not "in $X$". Also could you explain how it follows that in these two disjoint open sets in $Y$ we always have $f(y) > g(z)$ for any $y\in U_1$ and $z\in U_2$? I don't see how this follows from what you have above it. Thanks. Jul1 comment Let $Y$ be an ordered set in the order topology with $f,g:X\rightarrow Y$ continuous, show that $\{x:f(x)\leq g(x)\}$ is closed in $X$ I certainly believe you, I just wonder if maybe there is an error in the book and parts (a) and (b) were switched. Anyways thanks for the help, I should hopefully be able to figure it out from here. Jul1 comment Let $Y$ be an ordered set in the order topology with $f,g:X\rightarrow Y$ continuous, show that $\{x:f(x)\leq g(x)\}$ is closed in $X$ This is part (b) of the problem almost word for word, my problem is part (a), I'm not sure what to make of that.. Except that they use min instead of max. Jul1 asked Let $Y$ be an ordered set in the order topology with $f,g:X\rightarrow Y$ continuous, show that $\{x:f(x)\leq g(x)\}$ is closed in $X$ Jul1 comment Have there been efforts to introduce non Greek or Latin alphabets into mathematics? +1 for suggesting katakana. Jul1 accepted Possible errors in my professor's notes, Abel summation Jul1 comment Possible errors in my professor's notes, Abel summation Ohhhhh that's right! Ok cool thanks. Jul1 comment Possible errors in my professor's notes, Abel summation I made an edit 14min ago it's the 1 to t integrals that are the problem, not the 1 to N.. not sure if you saw that or not. The reason is that B(1) = 1/2 when you want the lower bound to give zero since B(t) = {t} - 1/2 by itself Jul1 revised Possible errors in my professor's notes, Abel summation edited body Jul1 asked Possible errors in my professor's notes, Abel summation Jun29 comment If $K$ is an extension field of $\mathbb{Q}$ such that $[K:\mathbb{Q}]=2$, prove that $K=\mathbb{Q}(\sqrt{d})$ for some square free integer $d$ Thanks! This makes sense. Jun29 accepted If $K$ is an extension field of $\mathbb{Q}$ such that $[K:\mathbb{Q}]=2$, prove that $K=\mathbb{Q}(\sqrt{d})$ for some square free integer $d$ Jun29 comment If $K$ is an extension field of $\mathbb{Q}$ such that $[K:\mathbb{Q}]=2$, prove that $K=\mathbb{Q}(\sqrt{d})$ for some square free integer $d$ I'm vexed by Zarrax's and Dylan's comments, but going off of anthonyquas if I can show $\alpha^2$ is an element of the rationals than $\alpha$ is a solution to the equation $x^2 - \alpha^2$ which is in $\mathbb{Q}[x]$. Is this the right direction? Jun29 asked If $K$ is an extension field of $\mathbb{Q}$ such that $[K:\mathbb{Q}]=2$, prove that $K=\mathbb{Q}(\sqrt{d})$ for some square free integer $d$ Jun24 comment What Topology does a Straight Line in the Plane Inherit as a Subspace of $\mathbb{R_l} \times \mathbb{R}$ and of $\mathbb{R_l} \times \mathbb{R_l}$ Thanks for this. Jun24 accepted What Topology does a Straight Line in the Plane Inherit as a Subspace of $\mathbb{R_l} \times \mathbb{R}$ and of $\mathbb{R_l} \times \mathbb{R_l}$ Jun24 comment What Topology does a Straight Line in the Plane Inherit as a Subspace of $\mathbb{R_l} \times \mathbb{R}$ and of $\mathbb{R_l} \times \mathbb{R_l}$ Excellent, this makes complete sense, thanks. Jun24 asked What Topology does a Straight Line in the Plane Inherit as a Subspace of $\mathbb{R_l} \times \mathbb{R}$ and of $\mathbb{R_l} \times \mathbb{R_l}$ Jun23 accepted If $\sum a_n z^n = f(z) = \sum b_n z^n$, What Can Be Said About the Coefficients $a_n$ and $b_n$