• @ptolemai
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    81 year ago

    fence sitting… what about points on the loop, are they inside or out?

    • darcy
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      31 year ago

      no point exists on the loop, a point can only approach the line

      • @[email protected]
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        21 year ago

        Why not? The line has to be at a point in space, so we can just define any point on the line

      • @[email protected]
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        21 year ago

        Don’t we usual define shapes with points? Like the corners of a triangle, since they have defined coordinates. Would a point at the same coordinate be inside or out?

    • @Migillope
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      1 year ago

      Depends on what you mean by “really complicated.”

      If you know Brouwer’s fixed point theorem in the plane and do not consider that to be complicated, then no. The curious can DM me and I will share a PDF of this little article (it is three pages).

      If you know some basic Algebraic Topology (homology), Hatcher gives a proof in section 2.B for the theorem (actually, he proves something even stronger) in a little under a page.

  • @RustyNova
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    110 months ago

    Next up: Pigeon hole theorem