cross-posted from: https://lemmy.ml/post/14733630

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Standard “they don’t know” meme format, featuring line art of “That Feel Guy” wearing a party hat standing in a corner while other people are dancing. An image of an icosahedron formed by three mutually perpendicular golden ratio rectangles sits in front of That Feel Guy. The caption text says “They don’t know that three mutually perpendicular golden ratio rectangles, with edges connecting their corners, form a regular icosahedron.”

https://en.wikipedia.org/w/index.php?title=Regular_icosahedron&oldid=1219666251#Construction

  • Tar_Alcaran
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    491 month ago

    I also didn’t know that, that’s awesome!

  • @JohnDClay
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    271 month ago

    Is it because the golden ratio contains the square root of three which is used in constructing triangles in 3d?

    Wait no, it uses the square root of 5 plus one, that is pretty magical!

    • @[email protected]
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      61 month ago

      I assume it’s because the GR has a ratio of the longer side to both sides summed. Although I can’t explain it further than that lol

  • wootz
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    1 month ago

    I knew this!

    On the off chance that one of you needs to model an Icosahedron / D20 in CAD, constructing three golden rectangles is often the easiest way to go, as it removes the need for calculating face angles.

    • @TheSlad
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      21 month ago

      I knew this too! And have even used it for that same purpose when I was into designing custom rubiks twisty puzzles a few years ago

  • FreshLight
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    111 month ago

    No fucking way!

    That’s the best piece of info I’ve had today!

  • @[email protected]
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    81 month ago

    I love to be pedantic so I’ll point out that it had to be 3 equal mutually perpendicular golden ratio rectangles

    • @[email protected]
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      61 month ago

      and they also have to not only intersent perpendicularly, but also each of their centers must coincide.

  • @BlueMagma
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    11 month ago

    Must have something to do with the fact that icosahedron is dodecahedron’s dual