Tagged Questions

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Pythagoras Theorem - Why a Theory? [closed]

Why is Pythagoras Theorem a Theory but not a Law? I mean we use it many times in School and to build stairs etc. and it has been proven however it is called a Theory.
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Name for Euclid, Book III, Proposition 21?

Euclid's Proposition 21 in Book III is something I learned in 11th grade. Is there a standard name for it? http://aleph0.clarku.edu/~djoyce/java/elements/bookIII/propIII21.html
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What is the meaning of “integral point”?

While reading this paper (http://cowles.econ.yale.edu/P/cd/d04b/d0473.pdf) I encountered the concept of "integral point", used first in definition 5.1, on page 34. Does anybody know more details about ...
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What do you call the 4-dimensional analog of a plane?

I keep wanting to call it a "space" but that conflicts with the 2-space, 3-space, 4-space, n-space nomenclature. e.g., in 3-space, you can hold one variable constant to get a 2-space "slice" (a ...
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Name of a Euclidean Geometry Theorem

There is a well known theorem in plane Euclidean geometry as follows, and I would like to know only the name by which it is known. Theorem: Let $ABC$ be a triangle. Choose points $D,E,F$ on the ...
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What do I call a unit vector parallel to a coordinate axis?

What do I call an arbitrary element of this set of vectors?  \begin{align*} \{&\langle 1, 0, 0 \rangle, \\ &\langle 0, 1, 0 \rangle, \\ &\langle 0, 0, 1 \rangle, \\ &\langle ...
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Term for Tetrahedron with Three Right Angles at a Point

Is there a name for the tetrahedron/pyramid (four vertices, four triangular faces, six edges) where three edges meet orthogonally at a point? Three of the faces are right triangles. Another ...
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A basic question on the terminology used in Desargues' Theorem

This is a pretty elementary concerning the terminology commonly used in Desargues' Theorem from plane geometry (or really, projective geometry). At least in some representative cases, I totally buy ...