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Mar
21
comment Locally disk-preserving charts?
A four-set Venn diagram (i.e. one that shows all 16 possible unions and intersections) is not realizable with disks in $\mathbb R^2$. If it is realizable with disks on a different Riemannian manifold, that would answer your question in the negative.
Mar
18
comment How to model continuous arrivals given a changing mean?
Time series analysis and forecasting is an entire branch of mathematical statistics.
Mar
18
comment Get any $3$ points in a plane from normal and one point
Take the three axis-aligned unit vectors $e_1,e_2,e_3$. Then $n\times e_1$, etc. are orthogonal to $n$ and at least two of them are nonzero. So $p+(n\times e_1)$ etc. are at least two other points on the plane.
Mar
17
answered Calculate sum of small values
Mar
17
comment Axis of a cylinder
If you are considering a cylinder which has two circles at the ends, the line joining the centers of the circles is the axis of the cylinder.
Mar
17
comment What if I swapped Infinity with zero on the 2-D Graph
Instead of drawing the graph of $f(x)$ you could draw the graph of $f(1/x)$.
Mar
16
awarded  Enlightened
Mar
16
awarded  Nice Answer
Mar
16
comment Problem with proving that sets can't contain themselves
Try applying the axiom of regularity to $\{A\}$, not to $A$.
Mar
16
comment Problem with proving that sets can't contain themselves
Sure, let $A = \{A, x, y\}$. Try applying the axiom of regularity to $\{A\}$.
Mar
12
comment Transform a nonconvex problem into a convex problem using perspective function
Try setting $y=1/t$ instead?
Mar
12
awarded  Nice Answer
Mar
10
comment Is the ridge of a sum of “ridged” functions on the intersection of the ridges of those functions?
$h^*=\max h=\max(f+g)\le\max(f^*+g^*)=f^*+g^*$.
Mar
10
comment Is the ridge of a sum of “ridged” functions on the intersection of the ridges of those functions?
Sure, if $h=f+g$ then $h^*\le f^*+g^*$. But at $(x_0,g_1(x_0))$ you have $h=f^*+g^*$, so it must be equal to $h^*$.
Mar
10
comment How to graph an implicit function by hand?
Without even a calculator? How shall we evaluate $\ln$?
Mar
10
comment Just got confused with what my friend asked (paradox and fake proofs).
$$\begin{align} \frac{\mathrm d}{\mathrm dx}(\underbrace{x+x+x+\cdots}_{\text{$x$ times}}) &= \underbrace{\frac{\mathrm d}{\mathrm dx}x+\frac{\mathrm d}{\mathrm dx}x+\frac{\mathrm d}{\mathrm dx}x+\cdots}_{\text{$x$ times}} + (\underbrace{x+x+x+\cdots}_{\text{$\frac{\mathrm d}{\mathrm dx}x$ times}}) \\ &= \underbrace{1+1+1+\cdots}_{\text{$x$ times}} + (\underbrace{x+x+x+\cdots}_{\text{$1$ time}}) \\ &= x + x \\ &= 2x. \end{align}$$ :)
Mar
9
comment Invertible function that “messes” order
I guess the word you're looking for is messy?
Mar
8
comment What is the probability that a point chosen randomly from inside an equilateral triangle is closer to the center than to any of the edges?
The vertices of the smaller triangle you drew are much closer to the edges of the original triangle than they are to the center.
Mar
8
comment Graphing $x^2+1$ over the complex plane
They appear to be plotting the graph of $z=\operatorname{Re}((x+iy)^2+1)$.
Mar
7
comment Is there a way to calculate absurdly high powers?
I was going to post the full decimal expansion in an answer, but unfortunately one is not allowed to post more than 30000 characters...