Yes, as others have already stated or implied, his interpretation of PEMDAS is WRONG- I didn't learn the initialism PEMDAS when I learned order of operations (ca. 1970), so I googled:
https://www.google.com/search?q=pemdas
EVERY link says multiply and divide are equal and you should go left-to-right, and likewise with addition and subtraction.
Then I even
(gasp!) read the comments. The first one says (bolding is mine):
I though you would have removed this video by now since it's all wrong. I know you like Physics more than Math but then you post things like this please make sure you are right.
PEMDAS stands for:
1. Parentheses
2. Exponent
3. Multiplication AND Division left to right
4. Addition AND Subtraction left to right
This is what I learned in school as a kid and if you follow this and you will never get two answers.
https://www.youtube.com/watch?v=y9h1oqv21Vs
You have to watch the video. No summary could cover the issues.
It's a MinutePhysics video sponsored by SquareSpace.
I think that the host is creating a straw-man, and that the amount of wrong he is is detrimental to his broader point.
Also, as someone who fiddles with web coding on occasion, I find the ad spot at the end a bit offensive. Especially considering the irony of the ad spot vs. his message in the video.
I've seen some of these Minute Physics things before, and I don't recall an ad at the end. I suppose this is all the big rage of the Internet, turning nouns into verbs and adjectives, in this case "monetizing" (perhaps also doing what you love, but trying to pay the bills at the same time).
...but the order of operations is for elementary schoolers...
It's also for anyone who wants to read mathematical statements involving more than one operator.
No one said there'd be math.
No one expected the mathish inquisition.
I don't know. The way he explains both PEMDAS and his "alternative" left me completely lost. And if I'm completely lost, that makes me kind of concerned for everyone else...
Just know that his explanation of PEMDAS is wrong.
I just don't know why we're blaming that on the Order of Operations. It's more of a broader curricula problem, in my mind.
Well, there's that too, but that's a different layer (oh noes, I'm lost in a twisty maze of layers, all different).
I don't think he's advocating actually using those parentheses, just understanding that they're implicitly there.
8 - 1 + 2 is not ambiguous if you understand that it's
(8) +(-1) +(2), not (8) - (1+2)
Actually it's not ambiguous at all if you understand that addition and subtraction are equivalent expressions and you should do the order of operations from left to right as taught. I'm not sure what he's getting at there.
Where he's "getting at " there is irrelevant, because he misunderstood (or maybe misremembered) PEMDAS.
I can see where that could happen: "Parentheses, then exponents, then ... " it's easy to keep saying "then" with each letter of the initialism, rather than putting the "and"s in where they should be.
The truly ironic part of this is his attempt to make a video that adds clarity may end up teaching people the wrong thing ("but you're supposed to add before you subtract, I know it's true because I saw it on the Internet").
I totally get why other people hate them.
