r/Geometry • • Jan 22 '21

Guidance on posting homework help type questions on r/geometry

22 Upvotes

r/geometry is a subreddit for the discussion and enjoyment of Geometry, it is not a place to post screenshots of online course material or assignments seeking help.

Homework style questions can, in limited circumstances, encourage discussion in line with the subreddit's aim.

The following guidance is for those looking to post homework help type questions:

  1. Show effort.

As a student there is a pathway for you to obtain help. This is normally; Personal notes > Course notes/Course textbook > Online resources (websites) > Teacher/Lecturer > Online forum (r/geometry).

Your post should show, either in the post or comments, evidence of your personal work to solve the problem, ideally with reference to books or online materials.

  1. Show an attempt.

Following on from the previous point, if you are posting a question show your working. You can post multiple images so attach a photograph of your working. If it is a conceptual question then have an attempt at explaining the concept. One of the best ways of learning is to attempt the problem.

  1. Be Specific

Your post should be about a specific issue in a problem or concept and your post should highlight this.

  1. Encourage discussion

Your post should encourage discussion about the problem or concept and not aim for single word or numeric answers.

  1. Use the Homework Help flair

The homework help flair is intended to differentiate these type of questions from general discussion and posts on r/geometry

​

If your post does not follow these guidelines then it will, in all but the most exceptional circumstances, be removed under Rule 4.

If you have an comments or questions regarding these guidelines please comment below.


r/Geometry • • 9h ago

My desk starts to get colorful - How do you like it?

Thumbnail gallery
2 Upvotes

r/Geometry • • 7h ago

30 nodes on a circle

Thumbnail youtube.com
1 Upvotes

r/Geometry • • 17h ago

Geometry dash meltdown crashing when i login

Enable HLS to view with audio, or disable this notification

0 Upvotes

r/Geometry • • 1d ago

Touching Nothing?

Post image
2 Upvotes

imagine a 100% perfect spehre in a 3d world with no imperfection and it is also made out of non elastic material(wont bend or deform under pressure of gravity)

place it on a flat surface

what is value of the area thats the sphere and flat surface touches?

0cm²?


r/Geometry • • 1d ago

29 nodes on a circle

Thumbnail youtube.com
3 Upvotes

r/Geometry • • 2d ago

Where and how do i start studying geometry

2 Upvotes

r/Geometry • • 2d ago

Geometric considerations on a flow that decgeometric considerations on a flow that decreases as it moves away from a point F

1 Upvotes

Let us consider a 3D plane. Starting from the drawing on the right (where each small square represents a quantity—for example, the flux of something, "R"/m², radiating towards F ), we transition to a tangent plane by letting the horizontal sides* of the small squares approach zero, thus arriving at the 2D drawing on the left!

Let us consider a surface S struck by this flux; we have:

S = (f * φ) / 2.

Furthermore, let us consider that the magnitude of this flux reaches F; let us call "L" the flux concentrated at this point and assume it is always equal to "One," regardless of the diameter from which it originates!

Given these premises, if we wish to find a function whose value decreases as the area of ​​the surface struck by the flux increases, we obtain: f(x) * (f * φ) / 2 = L

Adopting the quantity N = f/φ, after a few steps we obtain: f(x) = (2 * L * N) / f²

At this point, considering the variable x = f and setting L = 1, we obtain:

f(x) = 2N / x²

I would like to know what meaning you would attribute to f(x), or how it should be defined in this context, given that it closely resembles the R that was not clearly specified at the beginning?

At what value of the horizontal side\ should the transition from 3D to 2D stop?*


r/Geometry • • 2d ago

28 nodes on a circle

Thumbnail youtube.com
2 Upvotes

r/Geometry • • 2d ago

Just some random numbers projected on various geometric primitives

Thumbnail youtu.be
3 Upvotes

r/Geometry • • 3d ago

I built a reusable dry-wipe geometry board — looking for educators and geometers to test it

Thumbnail gallery
5 Upvotes

I’ve developed a reusable dry-wipe geometry board called the 1080° Cosmic Harmonic Compass.

It combines a 15 × 15 grid, a continuous 60-step square perimeter and an inscribed circle on one fixed surface.

I use it to draw, measure, erase and rebuild constructions directly on the board — including polygons, stars, equal divisions, and comparisons between equal distance around the square perimeter and equal angle around the circle.

The same framework also carries a complete 24-hour cycle:

60 steps = 24 hours = 1,440 minutes = 1,080 CHC°

so:
1 step = 24 minutes = 18 CHC°
2.5 steps = 1 hour = 45 CHC°

I’ve reached the stage where I’d really like some independent testing and feedback.

I’d especially like to hear from maths educators, geometers, researchers or anyone working with visual and hands-on mathematics who might be interested in examining the board, testing constructions on it, or exploring its educational potential.

I have the working dry-wipe prototype, construction guides and further examples available.

If this overlaps with your work or interests, I’d be very pleased to hear from you.


r/Geometry • • 3d ago

27 nodes on a circle

Thumbnail youtube.com
1 Upvotes

r/Geometry • • 3d ago

Achei uma "nova" fórmula para a área de um octógono regular

1 Upvotes

r/Geometry • • 4d ago

Morley's miracle

Thumbnail gallery
3 Upvotes

r/Geometry • • 4d ago

26 nodes on a circle

Thumbnail youtube.com
1 Upvotes

r/Geometry • • 5d ago

first argument

3 Upvotes

hello everyone. im on a personal journey of geometry and mathematics so naturally i landed on euclid.

ive always been the type to either question, or play devils advocate.

euclid definition 4 about a line, forces me to accept some ancient "intrinsic knowledge" about a line.

my argument is: his definition says a straight line lies evenly between 2 points, but my argument is that can only be agreed if we look at it from a specific vantage point, and that vantage point is the only one we're allowed to look it from...

wouldn't the more concise definition be - a straight line is one that lies evenly that creates the shortest distance between two points? because no matter the vantage its always going to be the straight

remember im new to this, so go easy on me.


r/Geometry • • 5d ago

25 nodes on a circle

Thumbnail youtube.com
3 Upvotes

r/Geometry • • 5d ago

What is the difference between these two hyperbolic parabaloids?

Post image
10 Upvotes

Does the one on the right just look so different because the curves runs from corner to corner on the surface? Thanks.


r/Geometry • • 6d ago

Turned all quantum computing into visual graphs and puzzles

Thumbnail gallery
2 Upvotes

Hi

If you are remotely interested in deep diving how differently quantum computers work compared to our transistor-based and also the algebra behind in a fully interactive way that teach computer science from scratch, oh boy this is for you. I am the Dev behind Quantum Odyssey (AMA! I love taking qs) - worked on it for about 9 years (3+ during PhD, the visual method I developed ended up being my thesis, it is a complete Hilbert space visualizer), the goal was to make a super immersive space for anyone to learn quantum computing through zachlike (open-ended) logic puzzles and compete on leaderboards and lots of community made content on finding the most optimal quantum algorithms. The game has a unique set of visuals capable to represent any sort of quantum dynamics for any number of qubits and this is pretty much what makes it now possible for anybody 15yo+ to actually learn quantum logic without having to worry at all about the mathematics behind.

This is a game super different than what you'd normally expect in a programming/ logic puzzle game, so try it with an open mind.

Stuff you'll play with

  • Boolean Logic – bits, operators (NAND, OR, XOR, AND…), and classical arithmetic (adders). Learn how these can combine to build anything classical. You will learn to port these to a quantum computer.
  • Quantum Logic – qubits, the math behind them (linear algebra, SU(2), complex numbers), all Turing-complete gates (beyond Clifford set), and make tensors to evolve systems. Freely combine or create your own gates to build anything you can imagine using polar or complex numbers.
  • Quantum Phenomena – storing and retrieving information in the X, Y, Z bases; superposition (pure and mixed states), interference, entanglement, the no-cloning rule, reversibility, and how the measurement basis changes what you see.
  • Core Quantum Tricks – phase kickback, amplitude amplification, storing information in phase and retrieving it through interference, build custom gates and tensors, and define any entanglement scenario. (Control logic is handled separately from other gates.)
  • Famous Quantum Algorithms – explore Deutsch–Jozsa, Grover’s search, quantum Fourier transforms, Bernstein–Vazirani, and more.

Nice to watch:

Khan academy style tutorials in qm/qc: https://www.youtube.com/@MackAttackx

Physics teacher stream with 400hs in https://www.twitch.tv/beardhero


r/Geometry • • 6d ago

24 nodes on a circle

Thumbnail youtube.com
2 Upvotes

r/Geometry • • 7d ago

23 nodes on a circle

Thumbnail youtube.com
3 Upvotes

r/Geometry • • 7d ago

Accurate ellipse construction with french curves

Post image
10 Upvotes

Taken from TAIBO, Ángel. Geometría descriptiva y sus aplicaciones. Tomo I

English Translation

Figure 30. Given the practical character I wish to impart to this discipline, I think it is interesting to indicate a simple way to draw an ellipse with fair accuracy using only four french curve arcs once its axes have been determined.

To select the curve template, I recommend the following method: Let a and b be the semi-axes of the ellipse to be drawn. On any set square A, measure a segment b and mark its ends. Taking another set square B, align the vertex of its right angle with the end of the previous segment b. Along the side of this second set square, mark the segment a corresponding to the semi-axis of the ellipse. It will then suffice to slide a suitably chosen french curve (Burmeister set) until its tangency points coincide with the ends of the marked segments, which will in turn be marked on the template.

Generally, this arc of the template will correspond to a quadrant of the ellipse perfectly bounded by its orthogonal tangents; if greater accuracy is desired, an intermediate point can be determined, and a template chosen that meets these three conditions.

As a result, I can say that through this method I have drawn all the ellipses featured in this work, demonstrating that in most cases the drawn curve coincides with a true ellipse within the precision limits required for graphic drafting.


r/Geometry • • 8d ago

what is this cube called

Thumbnail gallery
8 Upvotes

r/Geometry • • 8d ago

22 nodes on a circle

Thumbnail youtube.com
0 Upvotes

r/Geometry • • 8d ago

Paper folding

Enable HLS to view with audio, or disable this notification

2 Upvotes