Questions tagged [geometry]
For questions related to geometric shapes, congruences, similarities, transformations, as well as the properties of classes of figures, points, lines, angles.
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Schlafli symbols for antiprisms and crossed antiprisms
I'm looking for help from a Geometry expert. I asked this question on math.stackexchange but didn't get an answer I was particularly satisfied with.
I am familiar with Schlafli symbols for polygons ...
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How to justify formula for area of triangle (or parallelogram)
I'm going to be teaching my kids the concept of area soon.
The concept of area of a rectangle (or square), $\text{base} \times \text{height}$ is fairly easy to both explain and intuit: you can break ...
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Math textbook for secondary school using Logo like language
What math textbooks for kids do you know that use Logo or similar languages with visual robots like Turtle (in "The Turtle Geometry") that demonstrate space motions, transformations of all ...
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Math textbook for secondary school using Logo like syntax
What math textbooks for kids do you know that use Logo or similar languages with visual robots like Turtle (in "The Turtle Geometry") that demonstrate space motions, transformations of all ...
- 83
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When can students understand the intersection of two circles?
I'm interested in learning two transitions:
(1) When can students reason (intuitively, but accurately) to conclude that two circles in the plane
could intersect in $0$, $1$, or $2$ points, or are ...
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Comparison of two ways to introduce translation to 12-14 year olds
I consider pupils 12-14 years old, who are new to translation. On the other hand, they have been accustomed to placing points in a coordinate system, especially when studying relative numbers. In ...
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About a difficult exercise for 12 years pupils
You have to go from a point $A$ (start) to a point $B$ (arrival) by crossing a river $(d)$ and traveling as little distance as possible.
Pupils first do a search by trying several paths $1,2,3,4$ and ...
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Infinite descent method in geometry
What are the examples we can use to explain infinite descent as an efficient method of proofs in geometry?
I think one of the best may be proving medians of a triangle are concurrent by the infinite ...
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Textbook For a Course on Classical Geometry
I have been assigned to teach a first year course in geometry the next academic year. This course has been running for quite a while in the university, but of late, has been thought of as redundant ...
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Proof that volume of cone is 1/3 that of a cylinder [closed]
I am trying to verfy the formula for "cone volume" calculation. It is not clear why cone volume is 1/3 of a cylinder volume with the same bottom size and height. Is there any proof of the ...
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What are some common errors and misconceptions about the Pythagorean Theorem?
I'm teaching a geometry class and want to ensure my students understand the most common errors and misconceptions related to the Pythagorean Theorem and its applications.
I attempted an initial Google ...
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Is there a particular reason why segment addition postulate and partition postulate are two different things?
I could be wrong but those two ideas sound the same, just that the partition postulate is more general. There is also the angle addition postulate.
The segment addition postulate states that if three ...
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Geometrical verifications for Algebraic formulae
What is the importance of using approaches related to Geometric Algebra in teaching,is it only useful when introducing Algebra to the students or can it be helpful to improve creative skills in ...
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What benefit is there to obfuscate the geometry with algebra?
Consider:
In a right triangle:
sin(2x + 4) = cos (46)
What is the value of x?
The question above is from standardized tests for a geometry course. If my goal is to have students understand ...
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Is it correct to state that a cone has no faces?
Faces are attributes of polyhedra, so it doesn't make sense to ask how many faces a cone has.
Are there traditional scholars that use faces attached to cones? How do different countries deal with the ...
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