𧡠Untitled Thread
Anonymous at Mon, 18 Mar 2024 20:40:28 UTC No. 16085356
>getting filtered hard by fractions
my dreams...
Time to give up on physics?
Anonymous at Mon, 18 Mar 2024 20:46:36 UTC No. 16085368
>>16085356
>filtered by 4th grade math
yeah, it's over for you. start filling out job applications at gas stations.
Anonymous at Mon, 18 Mar 2024 20:48:28 UTC No. 16085373
>>16085356
Just rewrite fractional a over b as ((a)Γ·(b)). So pic would become ((2)Γ·(5))Γ·((3)Γ·(10)). Then just use BODMAS. Fractions aren't that hard.
Garrote at Mon, 18 Mar 2024 20:53:26 UTC No. 16085386
a/b = a*b^-1
(a/b)^-1 = b/a
Anonymous at Mon, 18 Mar 2024 20:56:22 UTC No. 16085392
>>16085368
I have no problem solving problems but this like cant be real
Anonymous at Mon, 18 Mar 2024 20:58:12 UTC No. 16085394
>>16085356
Do you have problems with other math or just fractions? If you struggle with math in general maybe your teachers as a kid were just shit, or you have dyscalculia or something. Not the end of the world but will make things harder
If it's literally just fractions there's probably some specific misunderstanding you have about them. If you can manipulate mathematical symbols to do algebra and calculus and whatever, *except for the symbols that represent fractions,* either you've learned something wrong about fractions specifically, or you have an extremely interesting neurological disorder.
Anonymous at Mon, 18 Mar 2024 21:02:59 UTC No. 16085398
>>16085394
Its hard to explain. Its like this with almost everything. I have zero problem solving any problems, as a kid I even did pretty well in math/logical competitions but I just cant wrap my head around anything. I ace all the practice tests I have but I still dont get it. Its like I dont understand whats going on "under the hood"
Anonymous at Mon, 18 Mar 2024 21:03:58 UTC No. 16085400
>>16085392
>I have no problem solving problems but this like cant be real
It's probably not, but a fuckton of people have trouble with fractions well past school.
Course a fuckton of people have trouble with PEMDAS well past school too.
Anonymous at Mon, 18 Mar 2024 21:12:12 UTC No. 16085410
>>16085398
What's the actual problem you're running into, then? I think a lot of people realize they're like that by college, as long as they're not actually studying mathematics it might not be an issue.
Anonymous at Mon, 18 Mar 2024 21:19:10 UTC No. 16085415
>>16085373
You're making it more complicated. Just remember fraction on the denominator will get flipped lol.
Anonymous at Mon, 18 Mar 2024 21:29:05 UTC No. 16085427
>>16085415
>You're making it more complicated
I'm not.
>Just remember fraction on the denominator will get flipped
That's not how shit technically works though. As an example 1β1Γ·1β0 does not equal 1β1*0β1.
It's a good shortcut in most situations but dividing by a fraction and multiplying by the inverse of the fraction is not actually the same thing.
Anonymous at Mon, 18 Mar 2024 21:39:03 UTC No. 16085456
>>16085427
>dividing by a fraction and multiplying by the inverse of the fraction is not actually the same thing.
They are, by definition. Division by a number is the same as multiplying by the multiplicative inverse of that number. the reason you can't manipulate 1β1Γ·1β0 to 1β1*0β1. is because division by zero is undefined (equivalently: zero has no multiplicative inverse), so the first expression is meaningless. You can move some symbols around, but if you start with nonsense, you'll end with nonsense.
Anonymous at Mon, 18 Mar 2024 21:40:52 UTC No. 16085461
>>16085356
If you want to do something and can't immediately do a small part of it you should give up. If you give up then you won because you are in control of the situation which means you can't lose. You are then entitled to begin hating the thing you wanted to originally do and say that it is shit and you don't want to do it anyway and the people that do it are idiots
Anonymous at Mon, 18 Mar 2024 21:48:52 UTC No. 16085484
>>16085456
>They are, by definition
They are not, by definition, or else 1β1*0β1 would equal 1β1Γ·1β0.
Also you originally just said fucking flip the fraction in the denominator and I just said inverse, not multiplicative inverse, even if you did want to get into a philosophical debate about whether something which doesn't fucking exist could be different from something which does or whatever fucking nonsense you are trying to argue to save face. Flipping the fraction does not fucking work in all fucking cases and rather than learning shortcuts that can trip you up in higher level math, it's better to just learn to do shit as written.
Anonymous at Mon, 18 Mar 2024 22:00:08 UTC No. 16085508
>>16085484
>They are not, by definition, or else 1β1*0β1 would equal 1β1Γ·1β0.
that's not what "by definition" means
>Also you originally just said fucking flip the fraction in the denominator
NTA, but flipping the fraction always works if the fraction you're working with is well-defined. "if the thing you're working with is well defined" is not usually specified when talking about math, for the same reason a cookbook doesn't remind you to check whether your ingredients aren't rotten, or a guide for changing a tire doesn't remind you that you need to have a car.
>I just said inverse, not multiplicative inverse,
Yes, you said inverse, I was more specific because there are technically multiple kinds of inverse and I am a pedantic autistic asshat. We are talking about the same thing.
Anonymous at Mon, 18 Mar 2024 22:03:33 UTC No. 16085515
>>16085356
I think Im actually starting to understand
Anonymous at Mon, 18 Mar 2024 22:06:02 UTC No. 16085521
>>16085398
dividing by a division makes no intuitive sense and you just have to accept it. if you have half an apple and you divide that half by half you get a full apple. why? you just do OK
Anonymous at Mon, 18 Mar 2024 22:11:36 UTC No. 16085527
>>16085521
how do you cope with that?
Anonymous at Mon, 18 Mar 2024 22:14:28 UTC No. 16085530
>>16085527
same way I cope with irrational numbers. math is just fundamentally flawed but it works in practise so I move on
Anonymous at Mon, 18 Mar 2024 22:30:44 UTC No. 16085562
>>16085508
>that's not what "by definition" means
You're really pulling a Clinton what is is? I don't think I've ever seen that level of clownery in the wild before.
Lmao.
Anonymous at Mon, 18 Mar 2024 22:33:04 UTC No. 16085568
>using the Γ· symbol ever
lmfao
Anonymous at Mon, 18 Mar 2024 22:40:38 UTC No. 16085589
maybe if we taught division in terms of multiplying by the reciprocal instead of cutting up apples this wouldn't be so confusing
Anonymous at Mon, 18 Mar 2024 22:49:16 UTC No. 16085615
>>16085589
but why does multiplying by the reciprocal work? Like whats going in the "background" like what exactly is happening and why?
Anonymous at Mon, 18 Mar 2024 22:50:17 UTC No. 16085619
>>16085562
"by definition" needs to invoke the definition. Division is usually defined, in discussions rigorous enough where it needs to be defined, as multiplication by the multiplicative inverse. You can't say that they are "by definition" not the things they are defined to be. That's not hair-splitting, that's telling up from down.
Anonymous at Mon, 18 Mar 2024 23:09:02 UTC No. 16085650
>>16085615
you're scaling the value to the denominator then taking numerator parts thereof. so a half divided by a half is scaling half up by 2 and taking 1 of them. dividing 1/2 by 1/4 is scaling the half up by 4 and taking 1 of them. if you're halving, you're scaling by 1 and taking 2 parts etc
Anonymous at Tue, 19 Mar 2024 06:45:06 UTC No. 16086085
[math]\frac{2}{5} \div \frac{3}{10}[/math] is how many times [math]\frac{3}{10}[/math] goes into [math]\frac{2}{5}[/math]. Because [math]\frac{3}{10} \times \frac{10}{3} = \frac{30}{30} = 1[/math], [math]\frac{3}{10}[/math] goes into 1 exactly [math]\frac{10}{3}[/math] times. To find how many times [math]\frac{3}{10}[/math] goes into [math]\frac{2}{5}[/math], we multiply how many times [math]\frac{3}{10}[/math] goes into 1 by how many times 1 goes into [math]\frac{2}{5}[/math].
Anonymous at Tue, 19 Mar 2024 07:20:00 UTC No. 16086119
3% of 57 = 57% of 3
[math] \displaystyle
\frac{3}{100}57 = \frac{57}{100}3 = \frac{3 \cdot 57}{100}
[/math]
Anonymous at Tue, 19 Mar 2024 10:31:52 UTC No. 16086292
>>16086085
>103
>10
>3
> times
lost me there
Barkon at Tue, 19 Mar 2024 10:33:24 UTC No. 16086293
>>16086292
103 is 37.3*3
Barkon at Tue, 19 Mar 2024 10:34:54 UTC No. 16086296
Scabs
Anonymous at Tue, 19 Mar 2024 10:42:41 UTC No. 16086304
>>16085398
I was like you, filtered hard by fractions in my teen years, and somewhat even past 20. I hated not understanding the deep roots of things and where they came from. I liked physics and natural science from childhood and was disappointed if I just gave it all up.
The remedy to this illness was Basic Mathematics by Serge Lang, cover to cover, all exercises, everyday until finished.
Anonymous at Tue, 19 Mar 2024 11:02:24 UTC No. 16086319
>>16085619
>"by definition" needs to invoke the definition
It does not, by definition. But even if it did, I FUCKING DID with Γ·((a)Γ·(b)). Which is obviously not *((b)Γ·(a)) in all cases.
Anonymous at Tue, 19 Mar 2024 11:21:23 UTC No. 16086337
>>16085521
>How many half-apples are there in half an apple?
One.
It's not even conceptually difficult.
Anonymous at Tue, 19 Mar 2024 12:29:25 UTC No. 16086409
>>16086319
1 / (a/b) = 1 * (b/a)
how is this not true?
the definition of division is the inverse of multiplication as long as the multiplier isn't 0
1 /(3/7) = 1 * (7/3) = 7/3
1 / (3/7) = (3/7)^-1 = ((7/3)^-1^)-1 = 7/3
Anonymous at Tue, 19 Mar 2024 14:11:31 UTC No. 16086526
>>16086292
A thing [math]\frac{10}{3}[/math] times is one third of that thing, ten times. Or equivalently, three of it, plus one third of it.
Anonymous at Tue, 19 Mar 2024 14:29:49 UTC No. 16086552
>>16086293
>90+21+0.9=103
wew lad
Anonymous at Tue, 19 Mar 2024 14:31:21 UTC No. 16086556
>>16085356
If you divide, you just invert and multiple. Whatβs there to be getting filtered about?
Anonymous at Tue, 19 Mar 2024 14:38:00 UTC No. 16086565
>>16085356
>fractions
You need to be 18 to post here
Anonymous at Tue, 19 Mar 2024 14:39:38 UTC No. 16086571
>>16085521
>dividing by a division makes no intuitive sense and you just have to accept it.
The question "how often does a 1/4 slice of a whole pizza fit into a 3/4s of a whole pizza" really doesn't make any sense to you?
>what if the slices don't have comparable sizes (e.g. one pizza is the size of an entire house)?
Then you scale one side beforehand
>what if you can't even compare them because one side is a pie, the other a pizza? (i.e. they'd have different denominators)
Then you take both sides and convert them into some abstract measure, like (continuing with the analogy), calling them both just "foodstuff".
Saying dividing by divisions makes no intuitive sense has to be the ultimate mathlet filter.
Anonymous at Tue, 19 Mar 2024 14:39:46 UTC No. 16086572
>>16085356
want a tutor?
Barkon !otRmkgvx22 at Tue, 19 Mar 2024 14:46:49 UTC No. 16086580
>>16086572
want a bawbeh
Anonymous at Tue, 19 Mar 2024 14:56:30 UTC No. 16086586
>>16085356
if you divide it by ten, it becomes ten times smaller
if you divide it by one, it remains the same
if you divide it by one tenth, it becomes ten times larger
Probably it's not the best rationalization, but maybe it can help you more than the better one.
Anonymous at Tue, 19 Mar 2024 19:06:05 UTC No. 16086885
>>16086319
if you think math is something you can win a debate against, you don't understand math. You're wrong on this point, no matter how right you think you are, and it's interfering with your ability to learn.
Anonymous at Tue, 19 Mar 2024 19:10:23 UTC No. 16086889
>>16086409
Why are you asking how something isn't true and then immediately replying with why it isn't true? The definition you're giving for division by fractions does not work for all values. The definition I gave does.
Anonymous at Tue, 19 Mar 2024 20:10:34 UTC No. 16086979
>>16086586
The thing is I already know and understand all this but like what the fuck is going?
Anonymous at Tue, 19 Mar 2024 20:57:25 UTC No. 16087014
>>16086979
I wouldn't say there's anything "going on;" it's not like division is just some shortcut to represent some mystical invisible process that's what we're really interested in. Division is just an arithmetic operation. It has certain properties. It doesn't have those properties because of anything else, it has them because we wanted an operation with those properties.
You can ask WHY an operation with those properties works to represent a specific situation, like cutting up an apple or whatever, but that will boil down to showing how the situation matches the operation. The operation comes first, it isn't based on any specific situation.
Anonymous at Tue, 19 Mar 2024 22:08:06 UTC No. 16087139
>>16087014
what I mean its like you can say 5*5 is 5+5+5+5+5. How do you elaborate divison by fractions?
Anonymous at Tue, 19 Mar 2024 22:14:44 UTC No. 16087149
>>16087014
like I cant visualize it or imagine it. I can "imagine" dividing and multiplying but I cant wrap my hands around dividing fractions by fractions. I have no issue with dividing fractions by normal numbers. Its way beyond me but it shouldnt
Anonymous at Tue, 19 Mar 2024 22:25:21 UTC No. 16087162
>>16087139
There might be something you're looking for that isn't this, but assuming b and c nonzero: [math]a\div\frac{b}{c} =a\div(bc^{-1})=a(bc^{-1})^{-1}=a(b
>>16087149
Hard to diagnose without knowing exactly how you're visualizing dividing and multiplying. If you can imagine dividing by a quantity, what about that image is incompatible with dividing by non-whole-number quantities?
Anonymous at Tue, 19 Mar 2024 22:52:20 UTC No. 16087206
>>16087162
idk I guess I dont see fractions the same way as normal numbers. Like it cant exist on its own. Idk if Im explaining it right
Anonymous at Tue, 19 Mar 2024 23:11:24 UTC No. 16087239
>>16087206
so you're fine with division by, say, 1.5 but not 3/2?
Anonymous at Tue, 19 Mar 2024 23:18:44 UTC No. 16087250
>>16087239
somehow yes
Anonymous at Tue, 19 Mar 2024 23:48:04 UTC No. 16087283
>>16086885
I'm not debating math. I was right on the math from the start. Motherfuckers are debating semantics. Badly. There is not a one to one correspondence between multiplication and division and you can't tell people to act like there is without noting the difference.
Don't tutor people badly then bitch about getting called out.
Anonymous at Tue, 19 Mar 2024 23:54:05 UTC No. 16087291
>>16087283
Division by a number is always the same as multiplying by the reciprocal of a number. There is no exception, none. There are times when division is undefined, but in those cases the reciprocal is also undefined, so there are absolutely no exceptions.
Anonymous at Tue, 19 Mar 2024 23:59:45 UTC No. 16087300
>>16087291
The original dumbshit claim was that you can just flip a fraction to go from division to multiplication.
>Just remember fraction on the denominator will get flipped lol.
Flipping 1β0 gives you 0β1, which last I checked is defined.
You are a dumb cunt.
Anonymous at Wed, 20 Mar 2024 00:03:00 UTC No. 16087303
>>16087300
You can flip any fraction. 1/0 isn't a fraction, because it's undefined.
Anonymous at Thu, 21 Mar 2024 00:22:04 UTC No. 16088872
>>16085615
>but why does multiplying by the reciprocal work? Like whats going in the "background" like what exactly is happening and why?
Read Allendoerfer and Oakley's Principles of Mathematics if you want a comprenhensive theoretical background, i.e., the logical answer to most of those "why" questions.
Anonymous at Thu, 21 Mar 2024 00:34:40 UTC No. 16088885
>>16087303
>You can flip any fraction
You can flip 0β1?
So 1*0β1 is the same thing as 1/1β0?
Anonymous at Thu, 21 Mar 2024 00:57:57 UTC No. 16088909
>>16088885
OK, you got me, I was not pedantic enough, and I lost the random internet encounter, unironically
Anonymous at Thu, 21 Mar 2024 01:17:45 UTC No. 16088938
>>16088885
1/0 appears naturally in denominators of combinatorics such as in binomial coefficient
Anonymous at Thu, 21 Mar 2024 17:10:22 UTC No. 16089643
>>16085356
If you're talking about pic, then I think this is just well-formed math -- you can arrive to it with some algebraic manipulation.