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Why do I keep thinking it's 9? Am I mis applying PEMDAS?
Maybe. It's been a long time but I thought it went Parenthesis, Exponents, Multiplication, Division, Addition, Subtraction left to right. 3 would be divided by 3 leaving 1. Then 1+1 = 2. Then 9-2=7.
Sorry should have been 7 I guess. I shouldn't need coffee to do this.
Yeah I see what I did wrong. I saw division but did multiplication.You've got the order right it's just the division by fraction that's off
3 divided by 1/3 is the same as 3 x 3/1
think of it like 3 *somethings* each divided by 3
Oh, man. Then, I definitely fucked up hahaMultiplication/Division as well as Addition/Subtraction are same steps. So you do all multiplication/division left to right, then all addition/subtraction left to right.
No, you're misapplying division.Why do I keep thinking it's 9? Am I mis applying PEMDAS?
The unfortunate thing about quaternions is that they're often relegated to only appearing in abstract algebra texts, where as they could easily appear as an expansion/addition to the complex numbers in more regular books. Then again most books don't really explain what complex numbers are. A cool fact is that there was a time when people thought about writing all of physics with quaternions until relativity came along. There's a novel by Greg Egan concerning if this had actually worked.I still don't understand the maths behind quarternonions, though, except apparently they can be used to do calculations for 3D transformations efficiently.
Yes, from what I read, 3D graphics books tend to be a much better intro than maths texts. I did take complex numbers far enough to do fourier transforms at one point, which made my brain hurt until I really grasped what was going on with them.The unfortunate thing about quaternions is that they're often relegated to only appearing in abstract algebra texts, where as they could easily appear as an expansion/addition to the complex numbers in more regular books. Then again most books don't really explain what complex numbers are. A cool fact is that there was a time when people thought about writing all of physics with quaternions until relativity came along. There's a novel by Greg Egan concerning if this had actually worked.
I was great at mental arithmetic until I got a calculator in 1982. Then it went downhill quite rapidly.I have a degree in math/economics, but I can't remember most of it. I find though, that I just have to take one of my math books from back then and start reading. So it's all in my head somewhere, just have to be refreshed.
Also many people think, that having a math degree somehow makes me good at doing calculations in my head. This as absolutely not true, in fact I suck at it.
In high school level math classes my fellow students, found it weird that I preferred to write 1/3 instead of 0,3333. I just found it easier to calculate that way.
I keep a copy of a textbook on math for technical careers around, which covers just about any mathematical application that I might need in daily life for when something completely escapes me. That happens more and more.I have a degree in math/economics, but I can't remember most of it. I find though, that I just have to take one of my math books from back then and start reading. So it's all in my head somewhere, just have to be refreshed.
I'm definitely weak at doing math in my head. As I didn't get interested in math until later in life, it was too late to hardwire that in. At least I have expertise on when to use hyphens.Also many people think, that having a math degree somehow makes me good at doing calculations in my head. This as absolutely not true, in fact I suck at it..
The slow and deliberate mindset probably serves you better than the quick and confident mindset I had initially attacking this problem.I keep a copy of a textbook on math for technical careers around, which covers just about any mathematical application that I might need in daily life for when something completely escapes me. That happens more and more.
I'm definitely weak at doing math in my head. As I didn't get interested in math until later in life, it was too late to hardwire that in. At least I have expertise on when to use hyphens.
The unfortunate thing about quaternions is that they're often relegated to only appearing in abstract algebra texts, where as they could easily appear as an expansion/addition to the complex numbers in more regular books. Then again most books don't really explain what complex numbers are. A cool fact is that there was a time when people thought about writing all of physics with quaternions until relativity came along. There's a novel by Greg Egan concerning if this had actually worked.
I’d also like to know how many people in their 60’s could still do this sum correctly in the 2020’s!
But think of the nostalgia factor.People in their 60s don't put up with bullshit like strangers calling them up and asking them to solve math problems
Well, if we are going down that road, I'd like to see if these surveys from the '80s and today actually exist, and if so, what the methodology was in each.I’d also like to know how many people in their 60’s could still do this sum correctly in the 2020’s!
The Orthogonal Series. Starts with "The Clockwork Rocket".I dig Egan, which book is that?