If you thought 8 ÷ 2(2+2) = ? was stupid and pointless, so did a lot of mathematicians.https://nyti.ms/2YKDk9f
-
-
Replying to @kchangnyt
I agree it’s pedantic AF, but you shouldn’t soft-pedal a ‘both sides have their point’ argument because the ‘controversy’ is driven exclusively by ignorance. Professionals and higher ed consistently prescribe how to handle this. We really need to be on the same pg on this stuff.
1 reply 0 retweets 0 likes -
Replying to @burnowt
If you read my essay, it’s exactly the professionals and higher ed who are exasperated by people slavishly using PEMDAS without understanding why or if it makes sense.
1 reply 0 retweets 0 likes -
Replying to @kchangnyt
What are the reasons and why does it make sense? I'll admit I really don't know the answers to either of those, and I mainly use it out of convention so that I can figure out what a badly written bit of code will do. Your article doesn't get into that.
1 reply 0 retweets 0 likes -
Replying to @burnowt
The conventions of PEMDAS are fine and indeed essential for performing calculations. The equation in question is deliberately constructed to mislead people to do the "wrong" thing. There's no there there.
1 reply 0 retweets 0 likes -
Replying to @kchangnyt
That's great, but you really do have me wondering: WHY does PEMDAS make sense? You've raised the question (by pointing out our ignorance), so why did a bunch of STEM guys at some conference somewhere many, many years ago decide this was the way to go?
1 reply 0 retweets 0 likes -
Replying to @burnowt
It works by definition. If there were no pre-defined order of operations, you would have throw parentheses everywhere to show the intended order of operations. What PEMDAS does is simplify the notation.
2 replies 0 retweets 1 like -
Replying to @kchangnyt @burnowt
All this equation is take advantage of the fact that when you learn PEMDAS, you haven't learned about implied multiplication yet with the parentheses but no multiplication sign.
1 reply 0 retweets 1 like -
Replying to @kchangnyt @burnowt
So the first step in PEMDAS is eliminate the parentheses. That's adding 2+2, which gives 8 ÷ 2(4). It's not unreasonable that people think, oh, I need to multiply the 2 and 4 to get rid of the parentheses. When you learn PEMDAS, that's not part of what you learn.
1 reply 0 retweets 1 like
In addition, in algebra, you learn that stuff connected by implied multiplication are factors that stay together. But in algebra, you never use ÷. All of the equations are written as fractions, exactly to avoid this ambiguity.
-
-
Replying to @kchangnyt @burnowt
So this is pathological mix of 5th grade math and algebra concocted to mislead people about the order of operations. That's not very interesting.
0 replies 0 retweets 0 likesThanks. Twitter will use this to make your timeline better. UndoUndo
-
Loading seems to be taking a while.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.