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

image description

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

  • @Dieterlan
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    58 months ago

    If you take three 3x5 note cards, and arrange them like in the picture, you can make a d20 die for D&D

    • themeatbridge
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      edit-2
      8 months ago

      Almost. A 3 x 5 card does not use the golden ratio. If you cut two inches from the long side, you get a square that is 3 x 3 and a rectangle that is 2 x 3. 2/3 is not equal to 3/5.

      The golden ratio occurs when a/b = (a+b)/a and it is also the ratio of the side of a pentagram to its diagonal. That’s why this works.

      • @radicalautonomy
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        8 months ago

        It’s still pretty close. 3(0.5(1+sqrt(5))) ≈ 4.854 ≈ 5, just barely over 3% higher.