May
19
awarded Custodian
May
19
revised If $f:X \to [0,1]$ be an onto continuous map and $\{f^{-1} (y)\}$ is compact then Is $X$ compact?
Cleared up unclear language.
Apr
23
answered Same Expansion for Different Functions! What's Wrong?
Mar
2
revised If $\tan x=\sin x/\cos x$ then what is $\tan 3x$ equal to?
fixed typo
Dec
10
awarded Enlightened
Dec
10
awarded Nice Answer
Dec
9
awarded Caucus
Nov
30
revised For $n\times n$ matrices $A,B,$ and $C,$ is it always true that $\mathrm{rank}(ABC)\leq\mathrm{rank}(AC)$?
added 80 characters in body
Nov
30
answered For $n\times n$ matrices $A,B,$ and $C,$ is it always true that $\mathrm{rank}(ABC)\leq\mathrm{rank}(AC)$?
Nov
21
comment Indiscrete space has trivial fundamental group
What have you tried? Have you considered which functions into an indiscrete space are continuous?
Nov
12
answered The jelly bean box problem
Nov
3
awarded Yearling
Sep
24
awarded Autobiographer
Sep
24
awarded Autobiographer
Sep
24
awarded Autobiographer
Sep
24
awarded Autobiographer
Sep
24
awarded Autobiographer
Aug
5
awarded Yearling
Aug
5
awarded Yearling
Jul
3
comment Prove that this affine transformation is a translation
I expect $\phi(P)P$ is the affine hull (line through) the distinct points $\phi(P)$ and $P$. This is why $\phi$ has to have no fixed points.
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