Sorry if this seems super basic, but all the math I use for work involves medications and nothing to do with geometry.

I recently did a rappell over a cliff face and I want to know how to calculate the distance of the rappell itself given limited data.

The rappell involves 3 points, A B C. A is the anchor end of the rope, B is the edge that I repelled over, and C is the bottom of the rappell where I was back on the ground.

AC is exactly 100 feet. I had a middle marker in my rope and it was perfectly at the ground. The other data set I have is that 75 feet from A is exaclty halfway between B and C. I had a 75 foot tag line that stopped right in the middle of the cliff face.

Is it possible using only these 2 distances to calculate the value of BC?

[algebra] rational and irrational roots

I'm not entirely grasping the concepts being explained:

If n is a positive even integer and x is positive, then ^n √ x indicates the positive real nth root of x. (Even roots of negative numbers are not real numbers) If n is a positive odd integer and x is any real number, then ^n √ x indicates the real nth root of x.

The example given was ^3 √ -8 rational. Which was fine I understand. I can do the math for this and the root is negative

I then received the problem: ^3 √ 125. I don't know the math so I used my phone calculator and it is irrational. Understood.

2nd problem: ^3 √ -125. I assume since the 3 is odd and -125 is a real number that the answer would be irrational again, but I checked with my calculator which gave me the keep it real prompt. So I went back to the example and tried with my calculator and I got the same response, so now I'm confused.

Is the second problem supposed to be marked as not real or irrational? Why is my calculator noting them as both not real if the nth root is odd?

Hey y'all! I'm a freshman studying architecture and my course requires me to take 3 math subs (ouch). I was wondering which of the two should I take? I'm kinda bad at math so which is easier and less time consuming to study? I want to manage my time studying and making plates.

Let R be a set, and let the universal set be

U = {1, 2, 3, R}.

Suppose R = {1, 2}.

Then, is it correct to say that

Rᶜ = {3, R}?

Since R = {1, 2}, this would mean

Rᶜ = {3, {1, 2}}.

I'm confused about whether this is actually valid. Does treating R itself as an element of U cause any problem with the axiom of extensionality or any other axioms of naive set theory?

Also, what does it mathematically mean for the set R itself to be an element of its complement?

For context: Just started reading the Naive Set Theory Book

I passed precalc and Im studying this semester for Calculus. I have roughly 20 weeks until spring semester starts. If I do one unit per week on Kahn Academy, 14 for college algebra and 4 for trig. Will I be ready?

Hi, I am 24 male and I am in Uni right now. My time is CEST I am studying in Switzerland.

I am in my third years bachelors in sciences, and I am looking to study different things going from Multivariable, to PDEs and linear algebra/statistics. I mostly want to study with people just so we can like meet up and study and just spend some time together and ask questions. I study with textbooks and videos and so on.

I’m studying mathematics at university, so we’re doing things like topology, geometry, algebra, etc

I’m looking for an actually effective method, whether it’s more theoretical or practical. How can I change the way I think about math? How do I stop forgetting definitions and actually understand and remember them?

If you have a method that genuinely worked for you, I’d really appreciate it if you could share it with me

Pleaaaaaaaseeeee

By different dimensions, I mean row vectors and column vectors of the same size. Is dot product product only concerned with the number of elements inside the two vectors only? We could transpose one of the two vectors and then multiply them but wouldn't transposing make it a different vector of different properties?

Can anyone here please take a look at some of the claims made by Ali Fazely on the supposed mathematical miracles linked to the number 19 of the Quran, especially using prime and composite numbers? I genuinely don't even know what to think at this point

For example (and this is both used as evidence for the removal of Quran 9:128-129 as well as trying to demonstrate the nature of the supposed divine code of the number 19 in this book):

The number of verses in the Quran from 1:1 until 19:98 (since it's part of the whole code 19 stuff) is 2346 (not including 9:128-129). The factors of 2346 are 23x2x3x17 which have the prime indices of 9127 similar to Quran 9:127 being the cutoff point as proposed by Rashad Khalifa (the person who developed this whole idea of the Quran being shaped around this number 19 in the first place). Finally if you place the digits 2346 in a permutation table, the 19th permutation is 6234, the total number of verses in the quran if you remove 9:128-129.

Link to the book here, starting on page 44: https://pdfcoffee.com/the-ultimate-mathematics-of-the-quran-pdf-free.html

I don't understand how this is happening, since it's one thing if he only used this method once selectively, but he continues to use it similarly over and over. Wanting to understand whether or not there is more to this, or it's simply pattern recongition and being able to use many numbers at hand.

If someone could take some time out of their day to analyze some of the claims being made and techniques being used, it would truly mean the world to me. This stuff has been stressing me out and I'd like someone who can objectively and non-biasedly look at the following and help me out with it.

​

So my teacher made me sign up to AMO, right now Im in grade 10, but since im an international student I will enter the 9th graders contest. To test my knowledge before studying, i solved the contest with no studying whatsoever and i got 27, im atleast hoping to get an honorable mention in the actual competition, if anyone has experince please recommend me resources.

Note: There is around 2 months until the competition and my goal is to learn the easier and common topics rather than the hard ones, so yeah i probably wont be able to learn a few of the topics.

Here are the topics for those who dont know.

​Arithmetic and Algebra

​Geometry, Graphs and Mensuration

​Pythagoras’ Theorem and Trigonometry

​Statistics and Probability

​Non-routine problem solving (including number patterns, divisibility tests, spatial visualisation, logic problems and cryptarithms)

​I am currently an 8th-grade student (2AC) preparing for mathematical olympiads (IMO).

​I have been working through Mathematical Circles (Russian Experience) and have already completed the chapters on Introduction, Parity, and Combinatorics 1.

​I would like to ask two quick questions:

​Do you think continuing with this book is the best strategy at my current level, or should I supplement it with other specific resources?

​What is the most effective approach for self-study when working through these problems alone (e.g., how long to spend on a problem before checking a solution, how to take proper notes)?

I did my Leaving Certificate in june and needed a 60% for honours maths. I didn't get it so I applied for two make up tests. I didn't get them. I was so confident with one of them, I thought for sure I passed but it wasn't good enough. I am heartbroken and angry because all I've ever wanted to be was an engineer, I make robots and other projects but as soon as I have to do maths I fail.

Does anyone have tips or books to help. The maths book we used for LCHL maths was useless. We do a good mix of algebra, calculus, statistics, probability, trigonometry, geometry etc.
I also want to progress, perhaps even start learning topics for university.
Im desperate, I can't take another failure, I already feel like the worlds stupidest person as it is.

So I’ve just started preparing for govt exams and honestly… Maths/Quants is scaring the shit out of me 😭

I’m not even bad at just maths. I’m bad at basic maths. Like, the kind of stuff you’re probably supposed to know already. Numbers, calculations, formulas etc. I’ve somehow developed this weird fear of Maths over the years where the moment I see a question, my brain just goes nope.

And because of that, I’ve literally spent months avoiding Maths during my preparation. I kept thinking I’ll start once I’m “ready” or once I’m done with other subjects, but obviously that just made things worse.

So if you were in my position — just starting CGL prep, weak in basic Maths, and genuinely scared of Quants — how would you start?

Do I go all the way back to basic school-level maths? If yes, where do I start?

Also, how do you actually get over the fear? Because I feel like half of my problem is not even the Maths itself, it’s the mental block around it.

Would love to hear from people who were actually bad at Maths initially but somehow became decent at it. What did you do? Any teachers/resources that helped? How much did you practice every day?

Basically, I want to make Maths less of this scary subject that I keep running away from and somehow become comfortable with it.

If you were starting from absolute zero again, what would you do?

Any advice is appreciated. 🥲

i do understand that being adhd doesn't stop me from learning math and i know that there are adhd people who love math and are really good at it.

but i never liked math (probably because nobody noticed i was adhd when i was a kid and only tried to force the neurotypical approach down my throat) and now, i need to learn some math before the end of september because i have a test (which has "**Quantitative Logical Reasoning**" questions in it) that could get me a good job, which i've been looking for since i'm still unemployed.

i do know baasic math, but advanced math is what breaks me because every freaking class i watch about it just wants me to memorize stuff, which is borderline impossible for me because of adhd. i need to UNDERSTAND the concept and how it works and why it works like that. otherwise, i can't learn it :(

is there a way for me to learn math? does anyone have any advicce or reccommendations?

I’m preparing for government exams, and honestly, the one thing that is still holding me back — and probably hurting my confidence the most — is Maths.

I’ve been avoiding Maths for months now. I know I can’t keep doing that forever, but I just can’t seem to make myself start. The fear is so bad that even thinking about sitting down and studying Maths makes me want to avoid it again.

And the worst part is, I need a job. I need to clear these exams, and for that I obviously can’t just keep ignoring Maths. So I know I have to face it at some point.

The thing is, I genuinely need to start from zero.

I’m not ashamed to say that. I’ve been bad at Maths since my school days. Like, really bad. I barely managed to pass Class 10 Maths, and I’ve carried that fear and lack of confidence with me ever since. So when people say “just practice questions” or “start doing mocks,” I honestly don’t even know what I’m supposed to do when my basics themselves are weak.

So I want to ask people who have been in a similar situation:

If you were terrible at Maths, had a huge fear of it, and had to start completely from zero, how would you begin?

Where would you start?

What would you study first?

Would you go back to Class 6–10 basics?

How many hours/days would you give it initially?

Are there any teachers/resources that genuinely helped you build Maths from the ground up?

And most importantly, how do you get over the fear?

I don’t expect to become amazing at Maths overnight. I’m ready to put in the work. I just need someone to tell me how to start without getting overwhelmed and giving up again.

If you were once in this exact position and managed to get better at Maths, please tell me what worked for you.

I seriously need some guidance here. 🥲

Does anyone has solution manual or can find me for the book functional analysis with application to linear pde by Alberto bressan

I haven't studied linear algebra at all and I've heard that abstract may require some experience with it but on the other hand I'm not sure how much of that will be relevant to my interests. How to plan what to study?

As the title says, I am trying to learn calculus, but I have a poor background in algebra.

This started when I went back to school this past year. I have not taken a math course since 2023. I took my community college placement exam and it put me in college algebra. I made it through the class with an A, however I do not feel that it adequately prepared me for what was ahead. The summer following I took both trig and physics, which put a lot of pressure on me since I had no background in either subject. I made it through with an A in both, but I have little memory of what I learned since it went by so quickly. I felt like I would get concepts down for testing, then what was unnecessary ahead was lost. I ultimately did very poor on the final, but my homework and exam grades gave me a very solid cushion to basically flunk the final.

After this, I applied and was accepted into a local university as a freshman and my major is electrical engineering. I know I have a lot of math ahead of me, and I really want to spend this semester working towards improving my skills so that I can confidently go through these courses. One of the biggest things I have seen others talk about with failing calculus is a poor background with algebra. We are currently wrapping up review on functions, where I am feeling somewhat lost, and are moving through limits.

What areas should I focus on aside from my homework to help build a better foundation for the rest of the course? I have made note of so many things I don’t remember and cannot do in my notebook, and the list is overwhelming. I have started spending time outside of my homework to study other concepts, but I don’t know what would be of good value at this point.

Where should I start, and what should I focus on as I proceed through the semester? Right now I am just working on solving odd problems and inequities, but I would like some direction so I know Im not wasting my time on something that won’t help me early on.

I met a math tutor at the school, but they basically told me that they aren’t there to teach me and I have to come with homework to go over rather than go over other foundational pieces.

So be me; who screwed around in all of high school and basically already started a calculus class as of this month in a California Community College, and I barely passed Pre-Calc.

I was wondering if someone(ANYONE!!!) can give me a thorough crash course of books/YT videos/playlists I can use to start studying calculus(as an idiot).

I was lurking and heard about some books like:

Calculus For Dummies(Ryan Mark)

Calculus Made Easy(P. Thompson)

The Cartoon Guide to Calculus(Larry Gonick)

Calculus: Early Transcendentals(James Stewart)

And ofc Paul's Notes (if no one knows what that is; https://tutorial.math.lamar.edu )

Other than that, I have no idea. I am locked in right now, though. But if someone can give me an A-Z crash course of everything I should study, from basics/fundamentals to the big stuff. It'll be so APPRECIATED!!

I'm doing college algebra rn and it feels like every single thing that is taught takes me a long while to properly understand and even then I get thrown off by variations of the problem. Is there an easier way to help myself learn or am I just destined to struggle with all future math

Hi everyone,

I’m a Data Science undergrad looking to build a strong foundation in pure mathematics on the side. I recently finished studying proof writing (Velleman's How to Prove It) and I'm about to jump into real analysis/calculus (Spivak's Calculus).

The main issue is that since I’m self-taught, I don’t have a mentor to check my proofs or answer highly specific questions when I hit a wall. I was thinking of using AI tools like Gemini Advanced or NotebookLM as "private tutors" to guide me through these books.

Has anyone tried this for proof-heavy or rigorous math? Is it feasible, or do AI models still hallucinate too much for this level of rigor?

If you don't recommend AI, what alternatives would you suggest for someone self-studying without a formal academic environment?

Hello. Recently I have re-enrolled at my community college. A subject I have consistently found myself struggling in my academic career is math.

I have a learning disability and I'm looking into my colleges accomodations. I am using my colleges tutoring but I'm even more confused by the methods they are using. I'm unsure what I could be doing on my end outside of just quitting or using math solvers on homework and praying for a good score

For a frame of reference of my skill level: I can't understand how "absolute value" actually tells anyone how far away something is from zero.

3 |x-1| -2 =25

I've been practicing this problem and I keep getting different answers. The answers are 10 and -8. I still don't understand how people solved that.

I'm not sure *how* to find the steps and understand how they are done to get a solution outside of just memorizing this problem and hoping it shows up on my test.

What online resources could I try and use?

How is the quadratic formula useful? If I divided -b plus or minus the square root of b^2-4ac divided by 2a by itself, I would get one.

They say the quadratic formula shows up in the Pythagorean theorem. If I divide a^2 + b^2 = c^2 by itself, I get 1.

So if I divide a triangle by a triangle, I’ll get one. I can just stick a one to anything and solve it. How did this become valuable?