## Can p → q |- ¬p ∨ q in intuitionistic logic?

Can you prove p → q |- ¬p ∨ q without using the law of the excluded middle or its equivalent? I'm going through a logic book (introductory) and I have an intuition that proving this isn't possible constructively, but I'd like a confirmation.
posted by Monday, stony Monday on Dec 1, 2016 - 14 answers

## Excel Formula to Weight Ratings By Number of Ratings?

How do I write an Excel formula to weight a rating by the number of ratings, so that a 4 with tens of thousands of ratings weighs more than a 5 with three ratings?
posted by WCityMike on Jul 5, 2016 - 13 answers

## Searching for a math learning book for children

Sometime within the last two years, I read a positive review of a mathematics book for children of at least kindergarten age that introduced math concepts using the number line as a conceptual focus. I'd appreciate any help in trying to identify this book.
posted by Svejk on Jul 5, 2016 - 3 answers

## Math education resources

I am aiming to create extracurricular programming for people of all ages (but I'm particularly focused on teens and adults) to illuminate the neat areas of math that aren't covered in school. (Graph theory, mobius strips, pascal's triangle, things like that.) However, I don't have a very official background in mathematics myself. 1) What resources can I use to teach myself about math in those areas, or math leading up to those areas? 2) What resources are out there for kids/teens/adults to increase their math awareness?
posted by azalea_chant on Jun 14, 2016 - 8 answers

## Counting 101 (and beyond)

Our three year old LOVES to say his letters and numbers. When he gets to Z, he triumphantly (and accurately) announces "and that's all the letters!" When he gets to 100 he proudly informs us, "that's all the numbers!" I've tried to tell him about 101, 102, etc., but he does not believe me. He would believe it if a YouTube video or app told him so. Any suggestions? (Yep, I know this is not a big deal. I just like watching the light bulb go on when he realizes just how big the world is.)
posted by slmorri on Apr 25, 2016 - 14 answers

## What sort of genius do I need to hire, and where can I find them?

I am in the process of trying to create a complex pricing calculator for internal use in our business. I have most of the data, however I am hoping to engage someone on a freelance basis to help me complete the data set, as well as give some expanded detail on how this data (pricing) can change geographically. What specific professions should I be engaging, and where can I find them? More information below the fold.
posted by sxtrumpeto on Feb 1, 2016 - 3 answers

## Learning math online

I want to learn math. I signed up for Khan Academy and I like the format a lot. I really like that there are short lessons that I can complete, and that the software automatically checks the answers and lets me continue when I completed a string of 5 good answers in a row (or something similar). I don't like the video explanations though. I'm just not a video person, I learn much better from text. Is there something like Khan Academy where you can do math exercises online but where the explanation is in text?
posted by blub on Feb 3, 2015 - 8 answers

## Help me solve this real-life math problem.

I need to use math to figure out how to fill my pill organizer correctly.
posted by Tin Man on Jan 12, 2015 - 12 answers

## Online resources for brushing up on basic math skills?

What are some good, free online resources for an adult who needs to brush up on basic math operations such as working with fractions, percentages and ratios? Other than Khan Academy. The more interactive the better.
posted by iamisaid on Dec 9, 2014 - 7 answers

I'm interested in teaching high school students mathematics through a tutoring agency. I have the required experience in mathematics, but very little in teaching. This doesn't seem to be a massive problem for many tutoring agencies, but I want to know: do you have any specific tips/advice about teaching mathematics? And more broadly, any advice about applying for and going to work for a tutoring agency?
posted by Quilford on Nov 26, 2014 - 4 answers

## Math-related field trip destinations for Bay Area HS students?

I teach math to high schoolers in the San Francisco Bay Area. I'd like to get them out of the classroom on a field trip to a local math-themed destination. Any suggestions?
posted by aws17576 on Aug 12, 2014 - 11 answers

## What are inter-disciplinary and atypical uses for math MSc?

I have just completed my MSc in mathematics in Europe. I do enjoy math, but I spent my uni years feeling like a autodidact hippie marooned on an island full of Mr and Mrs I-Want-A-Good-Job. My main interests revolve around humanities (literature/history/anthropology) and economics (but not finance), and instead of starting a "stable" well-paying career I dream about something inter-disciplinary. I am very open to earning little money and relocating just to do kind of work that engages those skills. What are some random uses of my degree?
posted by desultory_banyan on Jul 28, 2014 - 12 answers

## Math Careers

Non-obvious careers for someone with a B.S. in Applied Mathematics?
posted by anonymous on Jul 22, 2014 - 21 answers

## Chance of event with small sample size, based on larger related sample?

Can/how can one improve the estimate for a chance of an event with a small historical sample size by utilizing the chance of a related event with a large historical sample size? Example and half-assed guess inside.
posted by Flunkie on Mar 20, 2014 - 16 answers

## Why do we have order of operations in arithmetic?

Why do we have order of operations rules in arithmetic instead of just strictly evaluating expressions from left to right (possibly with parenthesis for grouping if we really wanted to change the order)?
posted by Reverend John on Mar 11, 2014 - 9 answers

## Educational mathamatics apps for adults that will work on an iPhone?

I am looking for adult-oriented iOS apps that will help improve my math skills.
posted by Gin and Comics on Nov 23, 2013 - 5 answers

## iPad math apps for a 10-year-old?

My son is 10 years old and going into 5th grade in the fall (but he usually does 6th grade math). He likes Stack the States, and we're looking for a math app with similar appeal. We already have Sushi Monster and his younger sister loves it, but I'd like something more challenging for him.
posted by The corpse in the library on Jun 25, 2013 - 11 answers

## Find standard deviation in Excel, but first develop a labor-saving trick

Help me with statistics and Excel. Especially help me if you know any labor saving methods. I want the median, mean and standard deviation for the average price of all items sold, but my spreadsheet-full-of-data doesn't tell me the price of each sale -- just the average price per store, and the number sold at that store. Something like this:
posted by croutonsupafreak on Jun 21, 2013 - 10 answers

## Help me understand fractions

posted by anonymous on Jun 19, 2013 - 29 answers

## Educate me on modern mathematics!

My math knowledge ends just past Newton. What books provide a good, relatively general-audience introduction to the past 150-250 years of problems and developments in mathematics?
posted by gallusgallus on Jun 10, 2013 - 7 answers

## What does a mathematician do all day?

I'm wondering, after breakfast, and a shower, and a commute, and coffee - what is next?
posted by Lownotes on Jan 24, 2013 - 23 answers

## The heck is a modular form?

For a work assignment, I need to come by a conceptual understanding of modular forms that's light on jargon and, ahem, actual math. If such a thing is possible.
posted by Zerowensboring on Jan 18, 2013 - 12 answers

## Teach myself Math virtually for the first time.

I'm a 21 year old college senior liberal arts major who has managed to slide by in school (and life) without ever really learning math beyond a middle school/very early high school level. For no reason in particular, I've decided that I want to get serious about bettering myself in the math department. How can I teach myself the academic math skills I missed out on?
posted by Krazor on Jan 15, 2013 - 19 answers

## Weighted mean

Mathematics-filter: If there are seven funds with various charges, how can I work out the allocation to these funds of a fixed amount so that the weighted mean charge is below a certain level and the allocations are of similar sizes?
posted by djgh on Dec 31, 2012 - 13 answers

## Poul la Cour?

Can anyone point me towards a good resource for learning more about Poul la Cour's work on wind turbines? Or other historic wind turbine work?
posted by teraspawn on Nov 13, 2012 - 3 answers

## What is the cardinality of the set of all people who shall expel us from the paradise that Cantor has created?

Sweet descriptions of the empty set?
posted by King Bee on Oct 12, 2012 - 12 answers

## My Trig Teachers Name Was Mr. Angle But That Didn't Make Him A Good Teacher.

My math skills are no where near where I'd like them to be. Can you recommend a self-paced math learning site? Pretty much any branch of math can apply.
posted by Ookseer on Aug 13, 2012 - 7 answers

## Operations in the Klasies Caves

I was helping my 4th grade age sister-in-law with her math homework, and came across a question that I couldn't figure out. Can you do it?
posted by symbollocks on Jul 13, 2012 - 13 answers

## Discrete mathematics for idiots?

Now that I'm back at college, I'm having serious trouble with an elementary course in Discrete Mathematics (for computer scientists). How can I complete this course?
posted by Foci for Analysis on Jan 31, 2012 - 29 answers

## I still KNOW the quadratic equation, just not what it means

I have forgotten basically all of math, and I want to learn it again from the ground up.
posted by showbiz_liz on Oct 19, 2011 - 28 answers

## What can I add to my math degree to improve my job prospects?

I have a B.S. in Math, but I haven't been able to find a job in my field. What can I add to my undergrad degree to be more competitive in the job market?
posted by ZeroDivides on Sep 21, 2011 - 12 answers

## Math ties?

Any good math or physics neckties?
posted by jeffburdges on Jul 20, 2011 - 13 answers

## Did Anyone Invent Some New Math Stuff So They Could Solve A Problem Which Then Lead To a Technological Breakthrough?

Can you cite any examples where a technological breakthrough wasn't possible until there was some sort of mathematical breakthrough?
posted by Brian Puccio on Apr 6, 2011 - 32 answers

## From teaching to tech - updating resume and skills

I have a Master's in math, and would like to get a job in the tech industry or a laboratory, but my resume is very teaching-oriented. I would like tips on retooling it to make myself more attractive. I also have several months to improve my skills.
posted by Earl the Polliwog on Apr 4, 2011 - 6 answers

## math finance text?

Any recommendations for a good graduate level text book for an introduction to mathematical finance course?
posted by jeffburdges on Mar 8, 2011 - 1 answer

## Never been near a university, never took a paper or a learned degree.

Why should I study math?
posted by Nomyte on Jan 22, 2011 - 8 answers

## Quantitative finance jobs for a pure mathematician

I'm a pure mathematician with a Ph.D. and I'm currently a visiting professor at a large state university. However, I'm looking to switch gears and get into the quantitative finance field. The problem is that I don't know anything at all about finance. I know that there are companies such as D. E. Shaw that hire mathematicians that don't have financial experience; what other companies should I look at? Is there any general advice you'd give someone in my position? Also, I have my Ph.D. from a well-regarded state school, but I'm not an Ivy-leaguer; does that put me at a disadvantage?
posted by Frobenius Twist on Nov 29, 2010 - 6 answers

## Dyscalculia and logic class

I have a learning disability (dyscalculia/mathematics disorder). Could I handle the formal language component of an undergrad Introduction to Logic class?
posted by autoclavicle on Nov 23, 2010 - 19 answers

## Recommend me a book on Cryptography/Cryptanalysis!

posted by zidane on Nov 14, 2010 - 12 answers

## Why doesn't the OED have better coverage of mathematical terms?

Why doesn't the OED have better coverage of mathematical terms? Is this an area they want to improve on, or have they drawn a line of obscurity somewhere that just leaves out more than I expected?
posted by ErWenn on Oct 5, 2010 - 9 answers

## Making math fun!

posted by gilsonal on Sep 7, 2010 - 24 answers

## An awesome vector geometry teaching website

I'm trying to find a website that teaches vector mathematics in lesson form.
posted by giggleknickers on May 3, 2010 - 2 answers

## Regular tessellations of Euclidean spaces

MathFilter: Is there a relationship between the number of dimensions in a Euclidean space and the number of regular tessellations of that space?
posted by jedicus on May 2, 2010 - 10 answers

## ount all the ways that 15 objects can be put into four piles so that each pile has a different number of objects in it.

"Count all the ways that 15 objects can be put into four piles so that each pile has a different number of objects in it." Is there a smart general method for solving problems like this? Feel free to assume uniqueness/non-emptiness of the piles if it helps. (Not homework)
posted by onalark on Apr 20, 2010 - 18 answers

## What do you love about zero?

My favorite number is 0. I have many reasons for this, but I want more.
posted by junipero on Apr 1, 2010 - 38 answers

## I am sick of having to say "I'm not good at math."

I have always had difficulty with mathematics. Now I'm in my mid-thirties and have gone back to school to study engineering. Things are not going appreciably better than they did the first time I went to university. What can I do to fill the gaps I have and become a skilled problem-solver? I want to go from being a C to being an A student.
posted by rhombus on Mar 24, 2010 - 30 answers

## Do we have to know Cramer's rule for the exam?

Why do people care about Cramer's rule?
posted by leahwrenn on Mar 3, 2010 - 8 answers