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[–] 119 points 2 years ago (19 children)

Student: "Hey, a shortcut! Let me first just walk around the long way so I can measure the length of the other two sides, multiply those lengths by themselves, add them together, and find out how much extra walking I've saved myself by taking the shortcut. Boy, this shortcut sure is saving me a lot of effort. Hooray Pythagoras!"

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  • [–] 42 points 2 years ago (6 children)

    Just because you do something so crazy fast in your head it seems obvious, doesn't mean you didn't do the thing you did with the thing.

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  • [–] 25 points 2 years ago (5 children)

    That’s beautiful who said that

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  • [–] 21 points 2 years ago (2 children)

    The hypotnuse is shorter than the other two sides combined. That is the usage here though

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    [–] 76 points 2 years ago* (last edited 2 years ago) (15 children)

    There's a college in Chicago, i think it's IIT maybe, that used aerial photography to map out the student cow paths, then they redid all the sidewalks to incorporate those paths.

    Edit: they ended up adding a building in a grassy area and maintained all the hall/walkways of the building in line with the sidewalks/cowpaths. Kinda neat.

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  • [–] 14 points 2 years ago (7 children)

    I'd be surprised if students didn't immediately make new paths off the new sidewalks

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  • [–] 25 points 2 years ago (6 children)

    why would they, desire paths happen because the initial pavements aren't designed well.

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  • [–] 13 points 2 years ago (2 children)

    We had that in my local park. There was a huge field that everyone walked through because it was much quicker than going around. So they finally made a sidewalk there (not with tarmac though, more like gravel and sand mix). Just a couple of weeks later there was a new path just parallel to this one. My guess is the problem was that the field was a bit hole shaped (sorry I don't know a better term in English) and this, as well just the nature of the sidewalk, led to it accumulating water puddles, and also it just turned into sandy/stoney mud when it rained. For bikes it was also just more comfortable to ride over the grass than over gravel. But it still felt like an asshole move.

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  • [–] 48 points 2 years ago (21 children)

    I wish I was taught about the usefulness of maths growing up. When I did A-level with differentition and integration I quickly forgot as I didn't see a point in it.

    At about 35 someone mentioned diff and int are useful for loan repayment calculations, savings and mortgages.

    Blew my fucking mind cos those are useful!

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  • [–] 24 points 2 years ago* (last edited 2 years ago) (8 children)

    That's one of the big problems with maths teaching in the UK, it's almost actively hostile to giving any sort of context.

    When a subject is reduced to a chore done for its own sake it's no wonder most students don't develop a passion or interest in it.

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  • [–] 11 points 2 years ago (7 children)

    In the US it's common to give students "word problems" that describe a scenario and ask them to answer a question that requires applying whatever math they're studying at the time. Students hate them and criticize the problems for being unrealistic, but I think they really just hate word problems because because they find them difficult. To me that means they need more word problems so they can actually get used to thinking about how math relates to the real world.

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  • [–] 19 points 2 years ago (2 children)

    Hated Algebra in high school. Then years later got into programming. It's all algebra. Variables, variables everywhere.

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  • [–] 18 points 2 years ago (1 child)

    Ehh I wouldn't say variables in programming are all that similar to variables in algebra. In a programming language, variables typically are just a name for some data. Whereas in algebra, they are placeholders for unknown values.

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  • [–] 9 points 2 years ago (7 children)

    The other use is as a door-opener; Learning these maths fundamentals enables you to pursue a stem degree

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  • [–] 11 points 2 years ago (6 children)

    as a door-opener

    You say that but they still need to teach you the "why". For example I did A-level maths which was a door to learning discrete maths in uni. Matrices, graphs, etc.

    In 20yrs as a software dev I never used any of it. Only needed basic arithmetic.

    To this day I've got no bloody clue what the point of matrices are.

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  • [–] 5 points 2 years ago* (4 children)

    They're used for manipulating vectors.
    Just like how in
    a×v
    the a makes the vector v longer or shorter, in
    M×v
    M can change the vector, for example rotate it.

    Just like vectors and other mathematical objects, matrices are purely theoretical concepts. There is no direct real-life meaning to them.
    However, there are a bunch of real-world problems where matrices can be put to use to calculate something meaningful.

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    [–] 43 points 2 years ago (7 children)

    One of my favourite names for anything is these being called 'desire lines'. It's so whimsical.

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  • [–] 57 points 2 years ago (5 children)

    Indeed! “Desire paths” is the name I heard. There’s a community, too: !desire_paths@sh.itjust.works

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    [–] 39 points 2 years ago (10 children)

    Idk, this really doesn't have to do anything with Pythagora's Theorem

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  • [–] 22 points 2 years ago (2 children)

    Beyond the general "hehe funny meme" Some seem to think there's some kind of math going on in people's heads other than "shortcut"

    The knowledge of Pythagoras or math doesn't factor in here at all. Toddlers do this.

    Having the knowledge just gives you fancy words for the resulting coincidental shape.

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  • [–] 6 points 2 years ago*

    Having the knowledge just gives you fancy words for the resulting coincidental shape.

    Isn't that basically all of physics? Just an abstract concept to describe something that sort of fits the rules we extrapolated from observations so far.

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    [–] 30 points 2 years ago (2 children)

    That footpath looks like a brachistochrone curve. Interesting.

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    [–] 20 points 2 years ago (3 children)

    all the student needs to know is c<a+b, not the actual formula or theory behind it

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    [–] 20 points 2 years ago* (last edited 2 years ago) (2 children)

    I think this is more a case of the triangle inequality in metric spaces, as you don't have to calculate any particular edge to see the shortcut, as well as that it applies to any even non-rectangular triangle.

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    [–] 17 points 2 years ago

    Triangle Inequality also!

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  • [–] 14 points 2 years ago (4 children)

    Now, I'm wondering if we have a thriving Desire Paths (that's what these paths are called) community somewhere on here.

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    [–] 10 points 2 years ago (3 children)

    this is actually the one thing i am glad to have learned in math class. saves me a lot of guesswork sometimes.

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