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PEMDAS is WRONG ! ? ! ?

submitted by AugustineOfHippo2 to mathematics 10 monthsJun 28, 2023 14:40:07 ago (+0/-0)     (mathematics)

I follow PEMDAS, but here are two videos proclaiming PEMDAS wrong:

https://youtu.be/FL6HUdJbJpQ

https://youtu.be/lLCDca6dYpA


I have always added additional brackets/parens to improve understanding, and have been the object of many people's derision because of it.
6/2(1+2) is a bit vague in my opinion, so I would write either 6/(2(1+2)) or (6/2)(1+2). I don't care if you don't like my extra parens, because you can't deny that my intent is explicitly stated and shown.


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[ - ] deleted 0 points 4 monthsDec 19, 2023 14:49:44 ago (+0/-0)

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[ - ] localsal 0 points 10 monthsJun 29, 2023 23:11:16 ago (+0/-0)

The first video is obviously a symptom of poor teaching or testing. Just because an acronym is spelled a certain way doesn't mean that it needs to be taught that specific order, and that students shouldn't be taught that multiplication is division and addition is subtraction (which they are)

The second video is just retarded in that they are taking a single printed line from a book and trying to base an entire cult following off it.

You will notice in her video she doesn't type her equations - she writes them on an empty screen. Obviously without any constraints, any equation can be written "correctly".

Yes, I'm sure the writers are lazy and don't want to include the parenthesis for added clarity.

Oh, but wait. Go find one of those books, and look for a complicated equation - not just one of the retarded fractions that this cunt points out. I bet there are gasp spaces, and maybe a multiplication sign, to point out different ideas when only using one line, right?

If this cunt were to follow up on her own assumption, what would be the answer to 1/1234?

Could it be 1/1x2x3x4? Or 1/12x34? Right? The permutations are endless. It isn't just retarded letters that specify things, right? She is retarded and a cunt for not thinking critically.

rant over. LOL.

[ - ] Love240 1 point 10 monthsJun 28, 2023 15:03:06 ago (+1/-0)*

Your parenthesis are in the wrong place for the last fraction.

6/2(1+2) = 1
6/(2(1+2)) = 1
(6/2)(1+2) = 9

This is because as you have written the first equation, the parenthesis is in the divisor, meaning it is actually separated out of that equation as 1/(1+2).

[ - ] AugustineOfHippo2 [op] 0 points 10 monthsJun 28, 2023 15:06:54 ago (+0/-0)

it would appear you didn't watch the videos...

[ - ] Love240 1 point 10 monthsJun 28, 2023 15:09:04 ago (+1/-0)

No, I'm on my phone and you have just simply written it out wrong. That's why you use the proper notation.

[ - ] AugustineOfHippo2 [op] 0 points 10 monthsJun 28, 2023 15:13:34 ago (+0/-0)

this is exactly the point the videos make. and exactly why I use extra parenthesis. the equation is not wrong.
6/(2(1+2)) = 6/(2(3)) = 6/6 = 1
nothing wrong there.

[ - ] Love240 0 points 10 monthsJun 28, 2023 15:15:13 ago (+0/-0)*

Watched your video, they are writing like it's IMPROPER programming. Like I said, that's why you use proper notation and contain your brackets.

If you write on paper it's easier to physically write the dividend and divisor where they are supposed to be, allowing you to understand that there are actually brackets around the entirety of the dividend or divisor, thus understanding the correct order in which the operation is to take place.

[ - ] deleted 0 points 4 monthsDec 19, 2023 14:54:32 ago (+0/-0)

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[ - ] Love240 0 points 10 monthsJun 28, 2023 15:28:44 ago (+0/-0)*

Yes there is.

This does not compile:
x = 6/2(1+2)
y = 6/(2(1+2))
z = (6/2)(1+2)

print(x, y, z)


This does:
x = 6 / (2 ASTERISK (1 + 2))
y = 6 / (2 ASTERISK (1 + 2))
z = (6 / 2) ASTERISK (1 + 2)

print(x, y, z)

The first gives a TypeError: 'float' object is not callable

You are trying to implicitly put the symbols for multiplication elsewhere, that's why the parenthesis placement is crucial. By using parenthesis and not physically writing the dividend and divisor as above or below AND by not physically writing the multiplication sign you are leaving all of that up to doubt.

EDIT: it won't let me use the asterisks appropriately. But that's exactly the point, you have to use the symbolism appropriately.

[ - ] localsal 1 point 10 monthsJun 29, 2023 23:25:13 ago (+1/-0)

I typed it into 3 newer calculators that accept line entries (rather than doing the calculation at every operator entry) - a ti-30XIIS, a casio fx9750GII, and a casio fx-115ES.

The TI calculator answered with 9, and the two casio calculators answered with 1.

The casio fx-9750 did this: 6/2(1+2) ==> 6/(2(1+2)) = 1
this is most likely a decision by casio to throw parenthesis around any numbers not separated by an operator. Not sure if that is a good thought process.

There is no way to try this equation on a majestic and obviously superior RPN calculator :)

[ - ] AugustineOfHippo2 [op] 0 points 10 monthsJun 28, 2023 19:33:01 ago (+0/-0)

Where in the videos does it specify programming?

[ - ] Love240 0 points 10 monthsJun 28, 2023 20:04:56 ago (+0/-0)*

Where do they specify otherwise?

I was basing my initial response on the body you wrote.

6/2(1+2) is a bit vague in my opinion, so I would write either 6/(2(1+2)) or (6/2)(1+2).

Yes, the first is vague, that's why I said you have to put the parenthesis in the correct place.

When writing divisions, the location of the parenthesis matter in the order of operations. If you are not specifying that this is 1(one) singular fraction (which this text is not doing) then you are proceeding using singular operations.

Which means the first is 9, the second is 1 and the third is 9.

If you are implying this is only 1(one) singular fraction, then the answer is 1, 1, 9

Again, this is simply a case of bad syntax practices with the assumption that parenthesis implies multiplication.

You just need to be consistent, parenthesis are your friend, even use brackets if necessary to avoid confusion.

[ - ] AugustineOfHippo2 [op] 0 points 10 monthsJun 29, 2023 07:50:40 ago (+0/-0)

your argument only proves the point being made in the videos.
and you are wrong:


online GDB using C

https://pic8.co/sh/CeZar5.jpg


dot net fiddle using C#

https://pic8.co/sh/kIuY8N.jpg

[ - ] Love240 0 points 10 monthsJun 29, 2023 07:55:08 ago (+0/-0)

That shows that I was right and that you had to add the asterisks.

Don't leave it up to confusion and just write it with the x or the asterisk instead of complaining about you having it wrong in the post body.

[ - ] AugustineOfHippo2 [op] 0 points 10 monthsJun 29, 2023 08:48:33 ago (+0/-0)

maybe in public school common core math, but in real math above 5th grade it is standard to write equations like y = mx+b without the asterisk or x to signify multiplication. even chicago public high school graduates would understand that to be y = (m * x) + b.
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[ - ] deleted 0 points 10 monthsJun 28, 2023 15:13:37 ago (+0/-0)

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[ - ] deleted 0 points 4 monthsDec 19, 2023 14:52:56 ago (+0/-0)

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[ - ] con77 0 points 10 monthsJun 28, 2023 15:53:41 ago (+0/-0)

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