/r/mathematics

r/mathematics is a subreddit dedicated to focused questions and discussion concerning mathematics.

/r/mathematics is a subreddit dedicated to focused questions and discussion concerning mathematics. Submissions should state and outline problems or questions about a given field or link to an especially insightful article about a mathematical concept.

/r/mathematics is a moderated community. Please read the submission and comment rules before posting.

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- Requests for help with homework.
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/r/mathematics

1

i am have real bad time understanding these topic can someone provide any material or lmk where can i learn them please

0 Comments

2024/09/01

12:55 UTC

12:55 UTC

8

For example

a^n + b^n + c^n + d^n = f^n

5 Comments

2024/09/01

06:41 UTC

06:41 UTC

0

Before I share it I would like a non violent discussion and if you did not get my method just say it down in the comments about the part you did not get instead of just disrespecting

log base 10 23571113171923(h)=13.3723800930….(let the answer be equal x)

y:x(ignore decimal part)+2 till it gets greater than 100

z:y last value+3 till it gets greater than 1000

a:z last value+4 till it gets greater than 10000

So basically I change +2 to +3 when two digits numbers change to three digits numbers and vice versa.

Now let’s only consider the decimal part of x:

Largest value of y=y.x=10^y.x =h

Largest value of z=z.x=10^z.x =h

Largest value of a=a.x=10^a.x =h

But you have to not just use.3723800930 as x but you have to find more values of it till infinity ahead of .3723800930 so that you can use that to make your answer precise and give primes in a sequence in a form like:23571113171923…..

The code to get more values of x aka to get more values of its decimal part:

from decimal import Decimal, getcontext, Context

import math

getcontext().prec = 110 # Set precision higher than needed to avoid rounding issues

number = Decimal('23571113171923')

log_result = number.log10()

formatted_log_result = f"{log_result:.100f}"

print(f"log10({number})={formatted_log_result}")

More precise code:

from mpmath import mp

mp.dps = 1100 # This sets the precision to 1100 decimal places

number = mp.mpf('23571113171923')

log_result = mp.log10(number)

formatted_log_result = f"{log_result:.100f}"

print(f"log10({number})={formatted_log_result}")

Note:Don’t use any type of approximations for the calculations involved in this method and always do precise calculations so that you get the prime numbers in sequence correctly again don’t approximate anything even the answers.

Note:After 13.37, one digit in decimal part of x=one prime number in the number h

License: Log and prime relationship © 2024 by Chaitanya Bankar is licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International https://creativecommons.org/licenses/by-nc-nd/4.0/?ref=chooser-v1

56 Comments

2024/09/01

03:10 UTC

03:10 UTC

5

This gif demonstrates the issue: Walker

The black dots are the exact coordinantes for the joints

My application recieve frames of a robot's movement. The raw frame data, specifically the angle of the different parts, need to be converted into angles from radices, this seems to work for the upper limbs, but not for the lower. The lower limbs hyperextend when frames start going in a positive direction.

The person supplying the frames insists that that is not an issue with data itself but something to do with how im processing it.

This is how im processing each angle value:

`radians * (180 / Math.PI)`

Here is a the structure of a raw frame:

```
{
"Hull angle": -0.08819633,
"Hull angular speed": -0.0050310385,
"Hull horizontal speed": -0.0026438022,
"Hull vertical speed": -0.021915445,
"Hip 1 angle": 1.0096797,
"Knee 1 angle": -0.49531424,
"Leg 1 ground contact": 0.0,
"Hip 2 angle": 0.5222587,
"Knee 2 angle": -0.027746916,
"Leg 2 ground contact": 0.0,
"Hull position": [4.628061294555664, 5.640387058258057],
"Leg 1 position": [5.038304805755615, 5.009975910186768],
"Leg 2 position": [5.1409478187561035, 4.185283660888672],
"Leg 3 position": [4.868274211883545, 4.873201847076416],
"Leg 4 position": [4.838898658752441, 3.8867387771606445]
},
```

One speculatation I have had is that when the "ground contact" value is 1 or true for a leg it is somehow supposed to trigger a change in how the data for the its respective lower leg is processed. Maybe the case, not sure.

This is code pretty much any kind of processing can be done, can be done conditionally etc.

Here is a screenshot showing how those values correspond to the visualization.

0 Comments

2024/08/31

17:32 UTC

17:32 UTC

2

I am trying to find where a circle intersects an angle where both lines touch but does not cross the circle. I was told to multiply the cosine of the delta with the radius then add to the radius for one intersection point. Then multiply the tangent of the delta with the radius and add it to the radius for the other intersection point. Is this right? I just feel like I'm missing something.

6 Comments

2024/08/31

17:24 UTC

17:24 UTC

3

Some time ago, I saw a video of a creative math teacher working with a group of interested children on various problems, such as summing the integers from 1 to 100. He was leading them through fascinating explorations in a very open-ended way. I believe another problem was on a chess board.

I believe the same individual posted a video of him doing the same in prison, with a group of initially not terribly engaged prisoners.

Does anyone know who this was or where to find the videos?

0 Comments

2024/08/31

16:10 UTC

16:10 UTC

0

I dont see why we cant have a number with more zeros that has a name. Like why not “Godogolplexian” that has like 10101 zeros in it??

14 Comments

2024/08/31

14:28 UTC

14:28 UTC

7

I have a function f(x,y) = |x-y| defined for 0<= x <= 1 and 0<= y <= 1. I want to describe the probability density function of f(x,y) given that x and y are uniformly distributed in their domain. Any help would be appreciated.

5 Comments

2024/08/31

13:48 UTC

13:48 UTC

8

I would appreciate if someone can help me with some clarifications. Why/how are stochastic processes different from the sequence of random variables that was used to prove the weak law of large numbers? If I understand correctly, stochastic processes are infinite sequences of random variables. Is the sequence of the sum of n i.i.d random variables, where n is indexed to the natural numbers a stochastic process? If no, why not?

8 Comments

2024/08/31

09:59 UTC

09:59 UTC

15

The thoughts of most normal people are scattered over a wide range of subjects, from daily life, to human interactions, to memories, future events, etc. etc. I have read of top tier mathematicians (and other world class achievers too) focusing exclusively on their craft to the (detrimental?) exclusion of all other matters.

As a not-too-serious student or practitioner of mats, when not actively sitting at a desk, and just going about your daily life, or just relaxing, how much of your mental bandwidth is occupied by math?

12 Comments

2024/08/31

06:16 UTC

06:16 UTC

10

I have seen many discussions of graduate programs in NA and Europe online and in real life, but almost no one discusses programs in Asia. As someone who immigrated to Canada from East Asia, I've also not considered this possibility until very recent. I have browsed through the admission details for a few universities but still want to get a general idea from people. I wonder if it is easier or harder applying to good universities as an international student, compared to applying to the US let's say. What are the advantages/disadvantages of this and what are some good recommendations? It would be even greater if you had this experience and is willing to share it. Thanks!

2 Comments

2024/08/31

03:32 UTC

03:32 UTC

2

Hi everyone,

I'm a math undergraduate student who is in the process of applying for masters programs in mathematics. I've come across a problem I never expected, which is writing a research proposal, which is required by essentially every department I'm applying to.

Specifically, my problem is I barely know anything about (higher) math to even begin writing. All guidance I saw online was something in the general nature of: Identify a gap of knowledge in the field, propose a methodology for closing the gap, write research methods, conclude with expected outcomes. But with my knowledge I can't even identify a gap in any field without just stealing ideas from the internet, while still knowing nothing about the subject. Reading math research papers is like deciphering a foreign language, and even if I had a concrete research question in hand, the latter steps for the proposal are still an enigma.

Can anyone give me some polite guidance on how to proceed with this? For reference, I am thinking of submitting a proposal in topology, but I am not concrete on this yet.

Thank you all for the kind advice in advance

0 Comments

2024/08/31

03:30 UTC

03:30 UTC

8

I am a first year Aerospace Engineering major. My first semester I am taking Physics 1 and its corequisite Calculus 1. I have ZERO prior training for calculus. So the messed up thing with physics is that we are learning topics that involve calculus topics weeks before they are taught in my calculus class so I'm studying some stuff early.

My question: are solving integrals kinda like memorization practice? Is it like trig identities where really I could explain the math behind them but there's little reason to so I just memorize and practice them? I booted up some Organic Chem tutor vids on integrals and it just seemed like memorizing some rules like with derivatives where they're acknowledging but not teaching the larger math behind them. I just want to approach studying them the right way.

10 Comments

2024/08/31

00:20 UTC

00:20 UTC

0

Helo, I just wanna ask if I am ok to pick Master in Mathematics on my future postgrad degree by having Bachelor of Secondary Education major in Mathematics as my undergrad degree. Thank you!

1 Comment

2024/08/30

18:46 UTC

18:46 UTC

302

I remember in 8th grade (2013) my math teacher talked about some japanese guy that invented a new form of math or geometry or something, and that it might be implemented into the curriculum once other mathematicians understood it completely.

Just wanted to know if this was real and what sort of an impact it made on math. Im not a mathematician btw. The memory just resurfaced and i thought it would be interesting to know.

178 Comments

2024/08/30

17:47 UTC

17:47 UTC

3

Do y'all think it's a good idea to take algebra (online) & statistics (in-person) at the same time? Today's the last day to drop & I'm not sure if I want to drop my statistics class. I'm a junior (supposed to have graduated this spring of 2024) but my freshman year something happened with my ALEKS test so I'm just now taking math for the first time at my university. I haven't looked at math forreal since my senior year of HS (2020) but this semester they gave me both my math classes that I need at the same time. I'm not the best at math, once we start pulling out graphs & the square root symbol I'm SO lost. I just finished intermediate algebra last spring (& I only passed bc the teacher was VERY I mean if one person answered a question right in class we ALL got bonus points on the next test) which is why I enrolled to take algebra online but they gave me statistics in person. Part of me wants to keep both bc l'm trying to take as much credits as possible bc l'm a year behind but then I don't want to set myself up for failure & end up failing if it turns out being too much. I'm currently taking 6 classes in all so idk. Is statistics are? What do y'all think?

5 Comments

2024/08/30

16:56 UTC

16:56 UTC

14

I’ve noticed that there’s a lot of math in writing and to me math is a language, not only something about numbers. I’ve noticed that that language to can be used in writing. It may not be numbers, but stuff like sets and the idea of mappings can be used. It can be used to organize storylines and find inputs and outputs in the story. What do y’all think or does something like this already exist?

22 Comments

2024/08/30

15:21 UTC

15:21 UTC

7

I studied math in college a while back. I plan on going back to school and getting a PhD in math but need to do some math and physics review first. I'm planning on picking a couple topics from below to self study. Would anyone like to join me?

- Conic sections
- rigorous calculus (Spivak)
- linear algebra done right
- intro ODEs
- intro PDEs
- intro complex variables
- intro mechanics
- intro thermal physics

6 Comments

2024/08/30

14:38 UTC

14:38 UTC

34

I am a high school student and I self studied, real analysis, some complex analysis, most till calc 3 and also abstract algebra, group theory and representation theory and many more. However I just can't get good scores on tests since I am not good at time management and panic when i`m short on time. Also am bad at memorising stuff so I get bad grades at many other subjects. I can solve imo problems at home but I just don't think I can with a time limit. So , I can't enter a high level university, can't get a nice award of some kind that would help me enter them . What should I do?

42 Comments

2024/08/30

13:55 UTC

13:55 UTC

1

I'm a third-year undergrad at a top US university majoring in math. I completed the requirements for a math degree in my third semester, have taken several independent studies and graduate courses, have published a research paper, have done an REU every summer thus far, and will probably take a few PhD qualifying exams this year. I intend to stay at my university and apply for math PhD programs during my senior year. I'm asking this question mainly for hypothetical reasons, but I also really don't want to finish off my general education requirements. This feels petty, but I would much rather just do four years of math/things I'm interested in. Unfortunately, my school won't give me a bachelors degree for that (they will though if you're in the honors program, so I also feel like I have somewhat of a disadvantage compared to many of my friends who can take whatever they want).

2 Comments

2024/08/30

02:31 UTC

02:31 UTC

9

Found these by accident. So, out of curiousity, is there study that if abc is prime, and WXYZ is prime, so that abcWXYZ or WXYZabc (concatenation of two or more smaller primes digits <arbitrary base?> in arbitrary order) is prime ?

13 Comments

2024/08/30

11:24 UTC

11:24 UTC

1

This summer I finished medical school with an MD degree and passed two USMLE steps. I want to pursue a mathematical PhD program more in statistics, random walks, and financial modeling. Is there hope for me to switch fields so dramatically? Where to start? Will PhD programs accept MD degrees?

I have always been interested in math and was reading advanced math textbooks (Linear Algebra by Jim Hefferon, Concrete Mathematics by Graham and Knuth, Principles of Mathematical Analysis by Rudin and The Fundamentals of Mathematical Analysis by Fikhtengol’Ts, A Classical Introduction to modern Number theory by Ireland and Generatingfunctionology by Wilf, Art of Computer programming I&II books by Knuth) I while reading this books tried to comprehended other topics in math. I also give try to solve exercises given in this books. I also as a hobby like to on my spare time love to wrestle with unsolved with unsolved problems in math. Actually this way I discovered to figure out much stuff that I don’t that is already discovered by someone and also to read math researcher papers.

I also know programming quite well. Starting learning python from age 12. Built different softwares and webpages both as my side projects and for university. Right know also know C++ and Rust.

Thank you in advance.

8 Comments

2024/08/30

10:08 UTC

10:08 UTC

28

I love math, I have a masters in economics, I majored in math in college, I want to do more math, but just for funsies. MUST I PHD? I have inquired about academia and it’s looking pretty bleak. Why can’t we all just do math for fun sigh

P.s. this is not a shit post I’m just frustrated and need advice. How do all the experienced math people do math for fun and not publication or capitalism

34 Comments

2024/08/30

01:13 UTC

01:13 UTC

2

I am a graduate student, I am currently doing an independent study in Tropical Geometry, but I more interested in Mirror Symmetry. My department doesn't have someone in that field, so I want to do a self study. I understand that there is a Mathematical side and Physics side to the subject. Obviously, I am more interested in the matematical side of things. anyone have any recommendations on resources on the subject? Also, is there any prerequisites that I might need?

3 Comments

2024/08/30

00:46 UTC

00:46 UTC

5

4 Comments

2024/08/30

00:06 UTC

00:06 UTC

69

I'm looking to build a comprehensive collection of math books that are essential for students and professionals, whether they're undergraduates, master's students, PhD students, or practicing mathematicians. But I don’t just want a list of popular titles I’m interested in hearing from people who have actually read these books and can share what they liked about them and why they would recommend them.

I should mention that I have a strong preference for pure mathematics over applied mathematics. It’s not that there’s anything wrong with applied math it’s just a matter of personal taste. Some people are drawn to pure math, others to applied, and some enjoy both. I happen to be in the first group, so I would appreciate it if the recommendations could focus more on pure mathematics. However, if there are applied mathematics books that you feel are truly indispensable, I’m open to hearing about those as well. What books have you found invaluable? It could be on any topic.

44 Comments

2024/08/29

20:57 UTC

20:57 UTC

3

Here’s what I’m trying to do: I have a set of products, prices, and quantity sold (large set) and I want to group similar products. As a “check” I want to look at the distribution of their prices—logic being products that are indeed similar/substitutes are similarly priced. Would it make more sense to look at the quantity-weighted variance or standard deviation? Does it matter that the prices are most likely not normally distributed?

3 Comments

2024/08/29

20:44 UTC

20:44 UTC

4

I am good at math till high school after that when I reached university i really started feeling difficult to learn maths till my high school mathematics has been taught to me using my native language but now in university they only teaching it in english.still I can understand most of them but because of my language barrier I am unable to understand some of the topics

The English I know is somewhat different from the one that is used in mathematics. I am just looking for an advise.

Sorry for my bad English.

1 Comment

2024/08/29

15:17 UTC

15:17 UTC

2

Hi everyone, i made this reddit post because i planned on getting really good at math. The reason why i decided is bc i’m about to start my first year at university in the engineering field and i dont feel ready to take on this new challenge with my actual level of mathematics. After reading the book of Scott H. Young “Ultralearning” i feel like being good at it is in my capacity. This is where you guys come into play ! My plan was to focus on my problems solving skills but i don’t know if it would be enough. Could you give me some advice on what i should start focusing on and what i shouldn’t ? Also it would be cool if you could share the hurdles you went through and how you overcame them. I wish you guys an amazing day !

1 Comment

2024/08/29

13:07 UTC

13:07 UTC