All Questions
Tagged with euclidean-geometry terminology
11
questions
3
votes
1
answer
2k
views
Does this hexagon theorem have a name?
Question : Do you know this property of a hexagon?
Consider the configuration: Six points $A_1$, $A_2$, $A_3$, $A_4$, $A_5$, $A_6$ in a plane and let six points $B_i \in A_iA_{i+1}$ for $i=1, 2,\dots, ...
- 1,454
13
votes
2
answers
2k
views
Is it a new discovery on conic section?
I discovered a problem in plane geometry (there are some nice special cases) as follows:
Let $ABC$ be a triangle and $\Omega$ be arbitrary circumconic. Let two points $A_b, A_c \in BC$, $B_c, B_a \in ...
- 1,454
6
votes
0
answers
317
views
Does this plane geometry theorem have a name (well-known)?
Consider three circles $(O_1)$, $(O_2)$, $(O_3)$. Denote the homothetic center of $\{$$(O_1)$, $(O_2)$$\}$ by $A$, the homothetic center of $\{$$(O_2)$, $(O_3)$$\}$ by $B$. Let $C$, $D$ be two points ...
- 1,454
18
votes
2
answers
1k
views
Emergence of the orthogonal group
Do we know what mathematician first considered, and perhaps named, what we call the group $\mathrm O(n)$, or $\mathrm{SO}(n)$, for some $n>3$?
I mean it specifically as group (not Lie algebra) ...
- 29.6k
3
votes
1
answer
589
views
Problem Understanding Euclid Book 10 Proposition 1 [closed]
this is embarrassing, but I am having trouble reading through Proposition 1 of Book 10 of Euclid's elements. I'm struggling with Euclid's terminology and don't have a clear picture of what divisions ...
- 595
60
votes
2
answers
4k
views
Does this geometry theorem have a name?
Start with a circle and draw two tangent circles inside. The (black) inner tangent lines to the smaller circles intersect the large circle. The (red) lines through these intersection points are ...
- 509
-1
votes
1
answer
485
views
Is there a commonly used short name for "squared Euclidean distance"? [closed]
In an optimization program I pass around distance values quite often. In my case these are simple 2D Euclidean distances $\sqrt{\Delta x^2+\Delta y^2}$. Since I want to perform the square root ...
- 202
1
vote
1
answer
301
views
Name of area between two parallel lines [closed]
Assume that there are two distinct parallel lines on a Euclidean plane. Is there a name for the zone between these two lines?
- 121
3
votes
4
answers
507
views
Terminology for polygons
As you may know term "polygon" might mean few different things
and its meaning has to guessed from context.
By some reason I have to use few of these meaning in one place.
So I converge to the ...
- 44.4k
32
votes
2
answers
1k
views
Term for "uncheckable constructions"
Is there a term for "uncheckable geometric constructions"?
Say, Angle Trisection and Doubling the Cube are checkable;
i.e., if the answer is given one can do finite Compass-and-straightedge ...
- 44.4k
4
votes
1
answer
606
views
What is the correct preposition? (And is there one?)
I just stumbled upon a linguistic problem I wasn't able to resolve via web search. Suppose we're given some geometric set $A$ and subset $B\subset A$. Isn't there a compact way of saying that there ...
- 3,503