• enkers@sh.itjust.works
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      4 months ago

      It took me up until reading your comment to get this one. “Is it that the scaling transformation only scaled the y-axis?? Oh…”

      • radicalautonomy@lemmy.world
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        4 months ago

        I teach these basic transformations as part of my middle school math classes, and I was completely loss as to why they didn’t include a reflection, but then I realized a reflection wouldn’t be that interesting because it could be indistinguishable from a translation.

        • untorquer@lemmy.world
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          4 months ago

          I was at a loss too as to where they source the “most common” when skewing is also extremely common

          • radicalautonomy@lemmy.world
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            4 months ago

            Scaling, in general, is the least common middle school transformation covered by state curriculum as far as depth of knowledge is concerned, at least where I’ve taught. Students just aren’t ready at that age to calculate something as sophisticated as the scale factor contributing to an object’s loss of size.

            • untorquer@lemmy.world
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              4 months ago

              I think the students are ready and quite capable of such sophistication. They’re just too distracted with sharing memes.

              • radicalautonomy@lemmy.world
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                4 months ago

                I think the students are ready and quite capable of such sophistication. They’re just too distracted with sharing memes.

                (Oh, I know, my middle schoolers do alright as long as our figures are two-dimensional, and my high school geometry students do very well; I just wanted to say the magic, fun, wink wink word again. 🙂)

  • justme@lemmy.dbzer0.com
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    4 months ago

    The second is not really scaled, and the second and forth have translation. Usually that wouldn’t be a problem for demonstrative proposed, if translation wouldn’t be shown explicitly. Can be fixed by introducing a canvas of the before/after picture

    • jol@discuss.tchncs.de
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      4 months ago

      The second is scaled in one axis, and had translation otherwise it would be hard to understand. And the rotation can be achieved by moving the origin of rotation.

  • maegul (he/they)@lemmy.ml
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    4 months ago

    Ok … I didn’t know this meme (too old and/or out of the loop I suppose) … so out of annoyance I looked it up …

    … and yea … as far as trolling is concerned gotta pay the game here … not sure it was worth 15 mins of my life but … kudos I guess

  • apocalypticat@lemmy.world
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    4 months ago

    Scaling looks like scaling+translation? And rotation looks like either rotation+translation, or scaling+translation?

    • Hjalmar
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      4 months ago

      Only the transformations one is correct. All the other ones seemingly also preform a translation, and even if they might be correct if you take the orgin to be slightly outside of the shape but that’s bad for educational purposes. Also this one makes the translation transformation look like the identity transformation.

      This last one might just be me, but shouldn’t shearing be included here?

      • barsoap@lemm.ee
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        4 months ago

        Congratulations, you found a complicated way to misunderstand a simple presentation. Then:

        All the other ones seemingly also preform a translation
        Also this one makes the translation transformation look like the identity transformation.

        You’re contradicting yourself there. Either each of the panels uses one coordinate system, in which case panel 3 is not the identity transformation, or the panels use two coordinate systems each, at which point scaling and rotation don’t include translation, and the translation panel uses the identity transformation.

        Or, you know, this is all not about teaching formulas, but words, and clarity of the rough idea, intuition, is more important than strict adherence to arbitrary things you just made up. I mean the axes aren’t even labelled why are you expecting the thing to be accurate. Who says this isn’t a log plot.

        This last one might just be me, but shouldn’t shearing be included here?

        Nope you’re right that’s the only proper critique to be had there. OTOH it says “most common” and if you don’t include perspective projection because you’re talking 2d only shearing isn’t that common at all.