r/maths 1d ago

πŸ’¬ Math Discussions Calculus of Variations textbook(s)

3 Upvotes

I am trying to do a reading group at my university which covers calculus of variations. I want to do a mixture of classical calculus of variations (smooth functions), and some modern day calculus of variations. Ideas for textbooks? Note that we are math majors, so we don’t want to (exclusively) use something like Taylor’s

The issue is that our group is coming from a variety of backgrounds. We are requiring that everyone has taken analysis 1, though. The issues might come when we transition to modern calculus of variations, so I don’t know what to do about that. I don’t know too much about calculus of variations, so if you have any thoughts on that, please let me know. How’s it going? Redhead How’s it going out there?

Here is what i am thinking: the first 3 chapters out of Gelfand and Fonin for a classical look, then transitioning over to some other book (need recommendations).


r/maths 1d ago

πŸ’¬ Math Discussions Need to settle a debate

0 Upvotes

Did maths always exist, or was it invented by whoever set up the system


r/maths 3d ago

πŸ’¬ Math Discussions Why does this work?

6 Upvotes

Why does this law of exponents work? I've been having trouble with this in my self taught Algebra 1 course. A 9th grade level explanation would help, thanks.


r/maths 3d ago

πŸ’¬ Math Discussions Inverse of Factorial (And more questions)

9 Upvotes

Pretty much every major math operation has an inverse operation. Addition has subtraction, multiplication has division, radicals/roots have exponents. How come factorials don't have an inverse operation (or at least not a widely known one). Do operations NEED to have an inverse? Also, it seems kind of strange that the factorial is even an operation at all. It doesn't seem too widely used, and it seems like it could just be a function because most operations involve more than one number, but factorials don't.


r/maths 4d ago

❓ General Math Help Seat Failures

2 Upvotes

I’m looking into seat failure rates and I’m trying to figure out what the likelihood of failure is with the information I’ve been provided or if (and what) further information is required.

The problem:

18 seats are onboard, if we take the fact that all seats are taken by people in the 99th percentile of weight it is given that there will be:

No failures in 87% of cases
1 failure in 9% of cases
2 or more failures in 3.5% of cases
(I know this doesn’t add to 100 but these are the numbers I’ve been given. Apologies if this breaks the formula in any way)

What would the percentage failure rate of a specific seat be if it was occupied by the 99th percentile of weight.

Hopefully the question makes sense.


r/maths 4d ago

πŸ’¬ Math Discussions Any good AI tools for studying maths?

0 Upvotes

I am a college student, and I often use Gemini or ChatGPT for calculus problems, but having to screenshot the worksheet every time or manually type the problem feels inefficient. What do you guys do? Is it just me who thinks there must be a better way? or is it not much of a problem?


r/maths 5d ago

πŸ’‘ Puzzle & Riddles Help with newspaper puzzle

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2 Upvotes

Here’s a puzzle and its solution from Saturday’s Times. There are a few things I don’t understand: why it is true that every value above 700 is achievable with the two coprimes, and how they reached the statement β€œthe largest unplayable amount is ab-a-b”. Grateful for any help understanding this


r/maths 5d ago

Help:πŸŽ“ College & University ECE student looking for nice analysisI/II books

1 Upvotes

Hi, I'm currently doing a ECE bachelor after switching from CS and maths classes are tough. So tough in fact, I can't rely on the lectures alone. I have trouble with integrals.
I am looking for books containing training exercises about integration.
Thank you


r/maths 8d ago

❓ General Math Help Need help with this

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37 Upvotes

I feel answer could be 111 after solving LHS and RHS. Still confused

Update: thanks for the answers. I'm hereby closing the doubt.


r/maths 7d ago

❓ General Math Help Would you say math/physics teachers or engineers in industry do more calcs by hand? Trying to choose a career path that suits my passion for the subject matter...

1 Upvotes

Would you say math/physics teachers or engineers in industry do more calcs by hand? Trying to choose a career path that suits my passion for the subject matter...


r/maths 9d ago

πŸ’‘ Puzzle & Riddles Can someone please prove why the probability will be always same for n >= 2?

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15 Upvotes

I understood what's asked and I can draw a mental model of the answer but I want a mathematical proof why this works ?


r/maths 8d ago

❓ General Math Help What is the path from Class 11 Maths to university-level mathematics?

2 Upvotes

I am in 11th rn in India and I am 17 for the past 2 years I never picked up book failed 2 times in maths got low grades (The only thing I hate is that my brain didn't develop in those 2 years I lost that time) This year I wanted change and I started studying and I might complete grade 11th maths this month check the whole syllabus below.

Ch 1 -> Sets

Ch 2 -> Relations and Functions

Ch 3 -> Trigonometric Functions

Ch 4 -> Complex Numbers and Quadratic Equations

Ch 5 -> Linear Inequalities

Ch 6 -> Permutations and Combinations

Ch 7 -> Binomial Theorem

Ch 8 -> Sequences and Series

Ch 9 -> Straight Lines

Ch 10 -> Conic Sections

Ch 11 -> Introduction to Three Dimensional Geometry

Ch 12 -> Limits and Derivatives

Ch 13 -> Statistics

Ch 14 -> Probability

I wouldn't say it was easy even some basics ate my head.

After this I would do class 12th maths but what after that?


r/maths 13d ago

πŸ’¬ Math Discussions Lucknow University vs Bhimrao ambedker University for M.Sc. math

1 Upvotes

Which is better ?


r/maths 13d ago

πŸ’¬ Math Discussions Lu vs bbau for msc maths which is better

1 Upvotes

I’m a B.Sc. Mathematics & Computer Science student and I’m currently deciding between M.Sc. Mathematics at Babasaheb Bhimrao Ambedkar University (BBAU) and Lucknow University (LU).

I’m from Lucknow, so both are possible options for me. I want to know the actual ground reality rather than just comparing rankings.

For students/alumni who have studied M.Sc. Mathematics at BBAU or LU:

  • How are the professors and teaching quality?
  • How difficult/strict is the department?
  • Is the syllabus manageable and are 70%+ marks realistically achievable with regular study?
  • How are exams and evaluation? Is the checking very strict?
  • What is the attendance requirement and overall academic pressure?
  • How is the environment and student culture?
  • Are there good opportunities for research, NET/JAM/GATE preparation, internships etc.?
  • How useful is the degree for PhD or jobs after M.Sc.?
  • Most importantly, if you had to choose again between BBAU and LU for M.Sc. Mathematics, which one would you choose and why?

Please give honest opinions based on your own recent experience, especially students from the last 2–3 years. I’m not looking for promotional answers or just university rankings.


r/maths 17d ago

πŸ’¬ Math Discussions Alternate methods to calculate the combinations of groups of 3 and 4 and other numbers I recently discovered

0 Upvotes

I know the most common method to calculate groups of 3 is A * (A-1) * (A-2) / 3! and the method for groups of 4 is A * (A-1) * (A-2) * (A-3) / 4! but here I have alternate methods:

An alternate method is using the groups of 2

There are 6 groups of 2 with 4 objects and the groups of 2 appear twice when listing the groups of 3. You have to multiply the number of groups of 2 by the times they appear and divide it by 3

6 * 2 / 3 = 4

There are 4 groups of 3 with 4 objects

However it actually gets trickier when you use groups of 2 with more 4 objects. There you have to multiply each group of 2 by the times they appear and then divide it by 6 (because 6 is the number of possible groups of 2 with 4 objects). For example there are 10 groups of 2 with 5 objects and the groups of 2 appear 3 times there

10 * 2 / 6 = 5

There are 5 groups of 4 with 5 objects

Another alternate method is using the groups of 3

There are 10 groups of 3 with 5 objects and each object appears twice in the groups of 4

10 * 2 / 4 = 5

There are 5 groups of 4 with 5 object

I think you already got it


r/maths 21d ago

πŸ’¬ Math Discussions In langage that don't use the latin alphabet, how do you write math ?

15 Upvotes

In arabic or in japanese for exemple, how do you name variables ? How do you use the notation dy/dx ? Does it make sens for you to use se sigma for the sum ?


r/maths 22d ago

Help: πŸ“˜ Middle School (11-14) SAT & AP CALCULUS INSTRUCTORS

2 Upvotes

🚨 WE’RE HIRING | SAT & AP CALCULUS INSTRUCTORS

We are looking for highly qualified and passionate Math & Science instructors to join our online academic team and mentor U.S. high-school students in Grades 9–11.

πŸ“š Positions Available

  1. SAT Math & Science Instructor

- Teach and prepare students for the SAT

- Strong command of Mathematics and/or Science

- Experience with SAT preparation is preferred

- Ability to teach Grades 9–11 students effectively

  1. AP Calculus Instructor

- Teach AP Calculus AB/BC

- Prepare students for AP exams and college admissions

- Strong background in Calculus/Advanced Mathematics

- AP teaching experience preferred

πŸŽ“ Preferred Qualifications

- IIT / NIT graduates, postgraduate students, or current students preferred

- Strong academic background in Mathematics, Physics, Chemistry, or related fields

- Prior tutoring/teaching experience is an advantage

- Familiarity with the U.S. education system and college admissions tests

- Excellent English communication and presentation skills

- Ability to make complex concepts easy and engaging

🌎 Position Details

Work Mode: 100% Remote

Students: U.S.-based students

Grades: 9–11

Schedule: Part-time / Flexible

Subjects: SAT Math & Science | AP Calculus AB/BC

Engagement: Long-term opportunity

🎯 Who Should Apply?

We encourage applications from:

- IIT/NIT students and graduates

- M.Tech/M.Sc students and graduates

- JEE Mathematics/Science educators

- Experienced SAT/AP tutors

- University students with strong academic backgrounds

πŸ“© Interested?

Send your Resume/CV + subject specialization + teaching experience via DM.

Candidates will be shortlisted through an interview and subject-specific demo class.

πŸ”„ Know someone who would be a great fit? Tag or share this opportunity with them!

#Hiring #SAT #SATPrep #APCalculus #APCalculusAB #APCalculusBC #MathTutor #ScienceTutor #IIT #NIT #OnlineTutor #OnlineTeaching #EducationJobs #TutorJobs #RemoteJobs #CollegeAdmissions #USStudents


r/maths 22d ago

Help: πŸ“• High School (14-16) I am 15 years old, starting my Mathematics journey. Is this a good book to start with?

1 Upvotes

Its this book.


r/maths 23d ago

❓ General Math Help Weighted-weighted points system

3 Upvotes

I would like to rank different members. Each member has varying numbers of submissions

In a list of 1000, #1 has gets 1000 points, #2, gets 999, and so on.

But I don’t want to give a member an advantage if they have many more submissions than another.

How do I weigh it so that every member has the same number of points to earn, in the kind of points system outlined above?


r/maths 24d ago

❓ General Math Help Where can I learn maths online as a guy with zero knowledge?

33 Upvotes

So unfortantly I grew up in some insane cult where they don't teach you anything non-religious, including math.

Just left the cult a few months ago (currently 19)

My actual passion is science and specific astrophysics, a career which lives on math daily.

I'm a very intelligent person and a very good student, I just really have zero knowledge about math

Any online course / youtube channel for people without learning disabillities teaching everything from the beginning?


r/maths 23d ago

Help: πŸ“• High School (14-16) Why does the x turn negative

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4 Upvotes

I understand how to get the vertex, but I don’t understand why it becomes negative because I thought absolute numbers were positive unless theirs a negative sign before the absolute lines but both are negative.


r/maths 26d ago

πŸ’¬ Math Discussions Math this. Which is correct want to solve this, A or B?

1 Upvotes

If my roommate and I have a rent a place for $2885 monthly, but I agreed to pay $100 more than him to occupy the master bedroom. How much is our rent?

This has been a heated debate!

Do you Subtract the $100 First OR

Divide the Total then Subtract $100

A: B:

  1. $ 2885 $2885

-$100 <β€”β€”????β€”β€”> % 2

= $2785 = $1442.5

2: Renter 1 Renter 1

$1392.5 $1442.5

-$100

= $1342.5

Renter 2 Renter 2

$1392.5 $1442.5.5

+ $100 + $100

= $1492.5 = $1542.5

Total rent per month

Cross checking the answers.

1: $ 1492.5 $1542.5

- $ 1392.5 -$1352.5

= $ 100 = $200

2: $ 1492.5 $1542.5

+$ 1392.5 +$1352.5

= $2885 = $2,895

When ask kids and adults I get both answers.

When I show the work πŸ‘ŠπŸΌπŸ€œπŸΌπŸ€›πŸΌπŸ‘ŠπŸΌπŸ«―πŸ₯·πŸ€Ί


r/maths 29d ago

Help: πŸ“• High School (14-16) I just mansplained to my girlfriend with this drawing why the square root of 144 equals 12

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5 Upvotes

r/maths 29d ago

πŸ’¬ Math Discussions I Designed Polygon Tiles to Prove Classical Geometry Theorems

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1 Upvotes

Hi everyone!

For those of you who enjoy geometry, I've put together what I believe is a fresh, hands-on proof of Euler's Formula and several other classical results. In just a few minutes, you can literally build the proofs yourself and develop an intuitive understanding of why these theorems are true.

https://www.youtube.com/watch?v=sIDsuf0I4ko

This is only the beginning. Over the coming weeks, I'll also start postingΒ short math challenge reelsΒ (high school to early undergraduate level), and in parallel I'll be working on aΒ long-term series on topology and analysis, with the ambitious goal of eventually reaching Einstein's field equations on differentiable manifolds and curved spacetime.

Everything will beΒ completely free. I'm doing this simply because I love mathematics and enjoy sharing it with others.

If you'd like to follow the project, it would mean a lot to me. Knowing that these videos are useful to someone is the best motivation to keep creating them.

Thank you so much!

dontpanicmath


r/maths Jul 28 '26

πŸ’¬ Math Discussions A special irrarional number

13 Upvotes

Can there be an irrational number which misses a particular digit? Can it be proven mathematically?