• wholookshere@lemmy.blahaj.zone
    link
    fedilink
    English
    arrow-up
    1
    ·
    edit-2
    2 months ago

    Except here you said here

    https://lemmy.ml/comment/13839553

    That they all must be equal.

    Tangents all be equal to the point would be exponential I thinks. So I assume you mean they must all be equal.

    Granted I assumed constant, because that’s what actually produces a “straight” line. If it’s not, then cos/sin also fall out as “straight line”.

    So I’ve either stretched your definition of straight line to include a circle, or we’re stretching “straight line”

    • ltxrtquq@lemmy.ml
      link
      fedilink
      English
      arrow-up
      1
      ·
      2 months ago

      Given r=f(θ), we are generally not concerned with r′=f′(θ); that describes how fast r changes with respect to θ

      You’re using the derivative of a polar equation as the basis for what a tangent line is. But as the textbook explains, that doesn’t give you a tangent line or describe the slope at that point. I never bothered defining what “tangent” means, but since this seems so important to you why don’t you try coming up with a reasonable definition?

      • wholookshere@lemmy.blahaj.zone
        link
        fedilink
        English
        arrow-up
        1
        ·
        edit-2
        2 months ago

        My whole point is that a “straight done”, in general, doesn’t exist in the first place. Because in general definitions are actually really hard.

        It’s not that it’s important to me. It’s that I’ve spent many parts of my day on the phone with the bank, and never should be taken for more than an asshole on the internet. Sorry if you thought I was more invested than that.