• amio
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    331 year ago

    Yeah, calling pi infinite makes me wanna cry, too.

    • @[email protected]
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      1 year ago

      If only mathematicians had a number for that. Ya know, the people famous for making names for things on average once per published paper, most of them completely useless.

  • Dippy
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    351 year ago

    Nasa uses 15 digits of pi for solar system travel. And 42 digits is enough to calculate the entire universe to atomic accuracy

    • Malgas
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      171 year ago

      And 65 digits is sufficient to calculate the circumference of the visible universe to within a Planck length.

  • @[email protected]
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    181 year ago

    Technically you can’t measure anything accurately because there’s an infinite amount of numbers between 1 and 0. Whose to say it’s exactly 1? It could be off by an infinite amount of 0s and 1.

    Achilles and the Tortoise paradox.

  • @[email protected]
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    251 year ago

    Not if your diameter is d/pi. Then your circumference is d, where d > 0.

    Check mate atheists.

  • @[email protected]
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    1111 year ago

    Easy. Take a wire that is exactly 1 meter long. Form a circle from the wire. The circumference of that circle is 1 meter.

    • Dippy
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      11 year ago

      Does this work with triangles too?

    • @[email protected]
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      11 year ago

      That approach works for area but not for perimeter, because cutting off the corners gives you a shape whose area is closer to the circle’s, but it doesn’t change the perimeter at all.

      • RandomStickman
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        1 year ago

        I think it’s because no matter how many corners you cut it’s still an approximation of the circumference area. There’s just an infinite amount of corners that sticks out

        • @[email protected]
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          251 year ago

          There’s just an infinite amount of corners that sticks out

          Yes. And that means that it is not an approximation of the circumference.

          But it approximates the area of the circle.

      • Armok: God of Blood
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        101 year ago

        Because you never make a circle. You just make a polygon with a perimeter of four and an infinite number of sides as the number of sides approaches infinity.

        • @[email protected]
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          21 year ago

          But if you made a regular polygon, with the number of sides approaching infinity, it would work.

      • @[email protected]
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        241 year ago

        It’s a fractal problem, even if you repeat the cutting until infinite, there are still a roughness with little triangles which you must add to Pi, there are no difference between image 4 and 5, the triangles are still there, smaller but more. But it’s a nice illusion.

  • @[email protected]
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    711 year ago

    Not true. If you define the circumference in terms of pi, you can define the circumference exactly.

      • Gnome Kat
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        441 year ago

        Putting things in base 10 is also a definition. Digits aren’t special.

        • @[email protected]
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          Was going to say the same. Also π isn’t infinite. Far from it. it’s not even bigger than 4. It’s representation in the decimal system is just so that it can’t be written there with a finite number of decimal places. But you could just write “π”. It’s short, concise and exact.

          And by that definition 0.1 is also infinite… My computer can’t write that with a finite amount of digits in base 2, which it uses internally.

          So… I’m crying salty tears, too.

          [Edit: And we don’t even need transcendental numbers or other number systems. A third also doesn’t have a representation. So again following the logic… you can divide a cake into 5 pieces, but never into 3?!]

      • @[email protected]
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        171 year ago

        That doesnt make a difference. You can find the exact circumference of a circle, you just cant express it in the decimal system as a number (thats why we have a symbol for it so you can still express the exact value)

  • JoYo
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    91 year ago

    Besides measuring it with a measuring tape.

  • @[email protected]
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    141 year ago

    The circumference of a circle with a diameter of 1 cm is exactly π cm. There you have it.

  • @[email protected]
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    1611 year ago

    More likely a mathematician would correct you instead of crying. Pi is not infinite, its decimal expansion is infinite!

    • LanternEverywhere
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      51 year ago

      Exactly, a fraction is completely as valid of a way to express a number as using a decimal.

      1/2 = 0.5

      They’re both fully valid ways to write the exact same quantity

    • @[email protected]
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      191 year ago

      This is the correct answer. Pi is known. What it’s decimal expansion looks like is irrelevant. It’s 1 in base Pi.

      • @[email protected]
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        71 year ago

        Yup, similar to the square root of two and Euler’s number.

        These are numbers defined by their properties and not their exact values. In fact, we have imaginary numbers that don’t have values and yet are still extremely useful because of their defined properties.

    • zkfcfbzr
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      861 year ago

      Plus even that isn’t enough: 10/3 has an infinite decimal expansion (in base 10 at least) too, but if π = 10/3, you’d be able to find exact circumferences. Its irrationality is what makes it relevant to this joke.

      A mathematician is also perfectly happy with answers like “4π” as exact.

      Plus what’s to stop you from having a rational circumference but irrational radius?

      Writing this, I feel like I might have accidentally proved your point.

      • @[email protected]
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        131 year ago

        Mathematicians taking a physics class and being told they have to round things. That’s when the tears start flowing.

    • @[email protected]
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      171 year ago

      The actual punchline here should have been “there is no known equation to calculate the exact perimeter of an ellipse”, then sucking tears from an astrophysicist