Ask MetaFilter questions tagged with algebra
http://ask.metafilter.com/tags/algebra
Questions tagged with 'algebra' at Ask MetaFilter.Sat, 18 Oct 2014 07:08:30 -0800Sat, 18 Oct 2014 07:08:30 -0800en-ushttp://blogs.law.harvard.edu/tech/rss60Best cargo cult symbolic equation editor?
http://ask.metafilter.com/270171/Best%2Dcargo%2Dcult%2Dsymbolic%2Dequation%2Deditor
You're an armchair scientist and you like reading scientific papers. A lot of the fun ones include a lot of equations. You'd like to be able to recreate those equations in a virtual blackboard. You'd select terms and be able to replace them with a library of previous equations you've made. The blackboard would enforce whatever symbolic manipulation rules are required to maintain consistency (because you sure won't be able to). If you replace a term with a number or a data input, it does the calculations necessary to display properly. What is it? The best tool for this will be able to do literally everything visually with the symbols, i.e., no text-based programming language required to use the features described here.tag:ask.metafilter.com,2014:site.270171Sat, 18 Oct 2014 07:08:30 -0800bigbigdogVicarious Math Pressure
http://ask.metafilter.com/269824/Vicarious%2DMath%2DPressure
My eldest child is starting high school. She is in the most advanced math class (a version of geometry) offered by her fairly demanding high school. But my eldest is struggling during the review of algebra -- rate problems, word problems, etc. Concerned because math is cumulative, and I don't want her falling behind. What can I do to help, both with math and with preventing her from becoming discouraged? My daughter is very intelligent. She tested into her advanced math class, and she has never received grades that were anything less than As. Now she's struggling a bit, though, and I would like to help her turn it around. I plan to have her speak to her teacher for his suggestions on how to improve her understanding and performance. If that fails, then I might try to find her a tutor, too, but it would be great to get the hive's thoughts on resources, books, programs, plans, or even just advice about how to help a 14 year-old girl through math that is more challenging than she has faced before. <br>
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Advice I may be considering internally but that I don't really need here: take her out of the advanced math; don't worry about math because it's not that important. Advice that would be wonderful: when I was a 14 year-old (or when I was parenting my 14 year-old) there was a similar problem that I solved by doing X, Y, and Z. Thanks so much.tag:ask.metafilter.com,2014:site.269824Fri, 10 Oct 2014 23:41:43 -0800Slap Factory4x+y+2z=100, x>y, y>z, x+y+z=j, 3x+z=k, j>k, j+k=100.
http://ask.metafilter.com/265560/4xy2z100%2Dxy%2Dyz%2Dxyzj%2D3xzk%2Djk%2Djk100
4x+y+2z=100, x>y, y>z, x+y+z=j, 3x+z=k, j>k, j+k=100. WolframAlpha can only give me alternative forms or a solution involving 'real and imaginary parts of z'. Is there a solution I can count on my fingers? I wish to buy a thing. The thing I buy will have two desirable characteristics: j, and k.<br>
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j comprises three sub-characteristics, while k comprises four sub-characteristics.<br>
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I have three levels for ranking how important these sub-characteristics are to me - let's say 'super important', 'kinda important' and 'meh, whatever'. Obviously, they are of decreasing importance.<br>
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I have rated the three sub-characteristics for j 'super important', 'kinda important' and 'meh, whatever'.<br>
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I have rated three of the four sub-characteristics for k 'super important', and the fourth 'meh, whatever'.<br>
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This means I have a total of four 'super important', one 'important', and two 'meh, whatevers'.<br>
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Finally, j is a little bit more important to me than k. If further defining these variables help, then I think they'd be about a 60/40 split, though I'm flexible. They can be equal if that helps. At this stage I'd settle for k being less than j if it means a solution pops out.<br>
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I would like to assign positive numbers to x, y and z, because I'm a bureaucrat, that's why.<br>
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So, <br>
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x>y (must)<br>
y>z (must)<br>
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j = x + y + z<br>
k = 3x + z<br>
4x + y + z = 100 (per cent)<br>
j + k = 100 (per cent)<br>
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I can't change the number of characteristics, sub-characteristics, or levels of importance. <br>
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I could make k=2x+y+z, and so change the overall equation to 3x+2y+2z, but I'm not smart enough to know if that helps. It didn't help WolframAlpha.</j>tag:ask.metafilter.com,2014:site.265560Tue, 22 Jul 2014 18:07:45 -0800obiwanwasabiWhere to get algebraic help?
http://ask.metafilter.com/263754/Where%2Dto%2Dget%2Dalgebraic%2Dhelp
I am working through the <a href="https://mooculus.osu.edu/">mooculus calculus one mooc</a> as a refresher (which I clearly need), and there is one thing I have run across that I just don't see. Can you help me figure out what is going on, and what I can do to work out future problems? <a href="http://www.youtube.com/watch?v=daKVqDF8hng&t=7m0s">In the video on Inverses of Functions, at about 7:00</a>, the professor simplifies:<br>
<br>
(6 +/- sqrt(6^2 - 4(-12 + h/5))/2<br>
<br>
to<br>
<br>
3 +/- sqrt(9 + 12 -h/5)<br>
<br>
and I just can't see how that is done. What is confusing me is the term "+12 - h/5" in the simplified square root. It seems to be off by a factor of two, since the -4/2 = -2, not -1. What am I missing in this case?<br>
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In addition, I am going to be working through this over the next weeks and have no doubt I will run into similar problems. Is there a website or software that will perform this type of simplification and show the steps? I have access to Matlab and Mathematica, but have never used them, if they help.tag:ask.metafilter.com,2014:site.263754Tue, 17 Jun 2014 20:01:42 -0800carpographerPhysics Study Guide
http://ask.metafilter.com/253735/Physics%2DStudy%2DGuide
For my pal...What is a good physics study guide for:
a) 1st semester algebra-based college physics
b) lots of solved problems
c) <i>without calculus</i>.
I remember liking Schaum's in undergrad, but I seem to recall it being calculus based.
Thx Hive!tag:ask.metafilter.com,2013:site.253735Sun, 15 Dec 2013 14:02:36 -0800j_curiouserBasic Math for Math Majors
http://ask.metafilter.com/251889/Basic%2DMath%2Dfor%2DMath%2DMajors
Hello! I'm a first semester grad student in applied math. I am a non-traditional student in a variety of ways (liberal arts undergrad, working full-time), and while I'm finding that I <em>intellectually</em> understand the concepts I'm learning, execution is being made difficult by my lack of fluency with algebraic manipulation and calculus. So, here's an excellent example. In a problem set this week, we were asked to find the expected value of <a href="http://imgur.com/LrnTDdQ">this god-awful density function</a>. (We had to integrate over 0-inf, solve for the constant <em>c</em>, then do another integration to find E(V).) (it's 2/(sqrt(pi)*sqrt(lambda)), if anyone cares).<br>
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This, no joke, took me 4 hours. At times I found myself just completely frozen about what to do next. I understand stuff like u-substitution and integration by parts, I'm just mindnumbingly slow at it, and I end up psyching myself out. <br>
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I need to get better and more automatic with this stuff ASAP. What's the best way to do that, relatively quickly? Are there problem banks somewhere I can use? I have some old books, is going through them helpful? Is there a cool iphone game or something?tag:ask.metafilter.com,2013:site.251889Wed, 13 Nov 2013 14:08:48 -0800downing street memo8th grade math tutoring options?
http://ask.metafilter.com/246063/8th%2Dgrade%2Dmath%2Dtutoring%2Doptions
Where can we find low cost math tutoring for 8th grade algebra? I've tried some web searches, but have not had much luck. My niece has been having trouble with math - late last school year, I got her a tutor, and the tutor got her through the end of the year with math - hurray! However, the tutor was really expensive, and I'd prefer to not have to do that again! ($40-50/hour, I think.)<br>
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She's doing online school, and it's a different one (K12, as oppose to Connections). We'll definitely get in touch with the school to see if they have suggestions for tutoring - the last school was completely useless, and kept putting us off, until she almost failed. My mom is her primary caretaker, and cannot do math at that level. My husband and I cannot tutor her either. So family tutoring is out.<br>
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I did see care.com, and there are some tutors listed for less (mainly college students, which is fine!) but how do you know if they are good or not? <br>
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Any suggestions welcome. I hesitate to do online tutoring, because her classes are online, and I feel like she's missing something trying to learn her math that way.tag:ask.metafilter.com,2013:site.246063Mon, 05 Aug 2013 11:33:45 -0800needlegrrlScale my function for a line graph
http://ask.metafilter.com/242747/Scale%2Dmy%2Dfunction%2Dfor%2Da%2Dline%2Dgraph
Math-filter: I have a line chart in Google Docs that plots three columns of data over time. Data in the first two columns ranges from 0-1000, but data in the third column ranges from 3-9. I'd like to "scale" Line 3 (maybe this is the wrong word?) to be able to compare its value over the same graph space as Lines 1 and 2. I think what I need to do is create a new, "scaled" column and plot that as Line 3 instead. Thus, in this scaled column, I believe 9 unscaled would be the same as 1000 scaled, and 3 would be the same as 0. Since this is a spreadsheet, I need something in the form y=<em>f</em>(unscaled Column 3 value).<br>
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That's all I've got, though, after half an hour of trying to remember my algebra, and then another fifteen minutes playing with Wolfram Alpha. Am I on the right track here? What's the function to scale Line 3?tag:ask.metafilter.com,2013:site.242747Wed, 12 Jun 2013 07:23:15 -0800electric_counterpointAlgebra: exotic identity values?
http://ask.metafilter.com/238714/Algebra%2Dexotic%2Didentity%2Dvalues
[mathfilter] please give me some example algebraic structures that are not commutative, with exotic identity values. I am creating an inventory of example algebraic structures of one operator that feature associativity, commutativity, identity values and all combinations thereof. My table is nearly full but for three entries:<br>
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- non-associative, non-commutative with different left and right identities<br>
<br>
- non-associative, non-commutative with both left and right identities, where both identities are equal<br>
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- associative, non-commutative, with either a left or right identity but not both<br>
<br>
(For clarity: a left identity is a value 0l such that 0l . x = x for all x, and a right identity is a value 0r such that x . 0r = x for all x. They may not be both present / the same if the structure is not commutative.)<br>
<br>
<strong>Do you know of example functions in these three categories?</strong>tag:ask.metafilter.com,2013:site.238714Mon, 08 Apr 2013 01:48:30 -0800knzCan a transcendental number raised to an algebraic power be algebraic?
http://ask.metafilter.com/236360/Can%2Da%2Dtranscendental%2Dnumber%2Draised%2Dto%2Dan%2Dalgebraic%2Dpower%2Dbe%2Dalgebraic
Can a transcendental number such as pi, be raised to an irrational, but algebraic power resulting in an algebraic solution? Complex solutions would be acceptable. There might be a quick proof here, or there might not be. - Thanks for any help you can offer answering this! (And I promise that this isn't for a class or anything like that!)tag:ask.metafilter.com,2013:site.236360Sat, 02 Mar 2013 06:33:30 -0800ch3coohClearly, this proves that I'm stupid
http://ask.metafilter.com/234391/Clearly%2Dthis%2Dproves%2Dthat%2DIm%2Dstupid
I can't seem to wrap my mind around the language of higher level math. Definitions, theorems, and proofs make me fall asleep, but I really do want to understand. Do you know of any good resources that can help me out? Back in high school (Canadian) I was a math whiz. I had no trouble with any of the concepts, including calculus in Gr 12. I can "do the math" and am good at problem solving. However when I got to university and started taking Number Theories, Abstract Algebra, etc., my logic suddenly disappeared on seemingly simple concepts. I've obtained my degree in CS already, somehow memorizing or handwaving my way through on my assignments and exams, but now I actually need to understand higher math for my current job.<br>
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For example, these are excerpts from one of my textbooks (A Concrete Introduction to Higher Algebra by Lindsay Childs):<br>
<br>
[on real numbers] "The real numbers form a complete Archimedean ordered field...Archimedean means that for every positive real number r there is a natural number n with n > r."<br>
[division theorem] "Given nonnegative integers a > 0 and b, there exist integers q> 0 and r with 0 <= r < a such that b = aq +r<br>
<br>
I thought I understood real numbers and division until I read these definitions and was also asked to prove them. First of all, my brain have difficulty just parsing out what's written; it's like a foreign language to me. Secondly I never know how to begin when proving things. I can somewhat follow along if there's an example in the textbook, but on my own I would be completely lost.<br>
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I'm not looking to take any classes in math or hire a tutor. Books or online resources would be good. At minimum I'm hoping to at least be able to read through a math textbook and actually understand the explanation.tag:ask.metafilter.com,2013:site.234391Thu, 31 Jan 2013 20:35:00 -0800lucia_engelThe use of Linear Algebra in Programming.
http://ask.metafilter.com/231710/The%2Duse%2Dof%2DLinear%2DAlgebra%2Din%2DProgramming
I just finished my first course in Linear Algebra. I know a fair amount of Python. Please help me come up with a project that combines the two. This past Fall semester, I took Linear Algebra I, a 200-level Math class at my school. (The next class, sequentially, is Linear Algebra II -- a 300-level class which is much more proof based.) I don't want to list everything that I learned, but I will say that the course covered a lot of material, and was quite rigorous.<br>
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Through the lectures, my professor would frequently reference Linear Algebra's application to computer science/computer graphics (e.g. how each pixel in an image can effectively be manipulated as an entry in a matrix). <br>
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Likewise, I want come up with a project that combines my newly acquired knowledge of Linear Algebra, with my ability to program.<br>
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A couple of notes with regards to the type of project that I am looking for:<br>
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1. I'm not really interested in game design or computer animation (and I know that both are predicated on Linear Algebra).<br>
2. I really like databases. In addition to Python, I know/am learning SQL -- I would love something of the sort that combines matrix manipulation with querying a database (if this is even a thing.)<br>
3. I'm learning Django, so any idea that involves building a (not too complex) web app would be great.<br>
<br>
Thanks a lot!tag:ask.metafilter.com,2012:site.231710Sun, 23 Dec 2012 10:46:06 -0800lobbyistAlgebra Question
http://ask.metafilter.com/229095/Algebra%2DQuestion
Can anyone help with an algebra question I am trying to help my neice with her homework. (9/2m) - (m+4)/4m = 5/36<br>
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11th grade algebra- do you multiply entire equation by 2m? lowest common denominator? help. An explanation would be great and also any websites that help with algebra would be great too. Thanks.tag:ask.metafilter.com,2012:site.229095Sat, 17 Nov 2012 11:35:42 -0800Summer FallNeed help finding an easy-to-follow Algebra textbook
http://ask.metafilter.com/226347/Need%2Dhelp%2Dfinding%2Dan%2Deasytofollow%2DAlgebra%2Dtextbook
Introductory Algebra Course - book recommendations? I'm now back in university, after being away for 3 years. Hurray! During my first term back (winter term), I need to take an introductory Algebra course in order to meet a prerequisite for an upper-year Psychology research class. The problem is, I haven't taken any Math classes since high school (so well over 5 years) and it has never really been my forte. No doubt it, this course is making me incredibly nervous. To top it off, the textbook required ("<a href="http://www.amazon.ca/Mathematics-Applications-Margaret-Lial/dp/0321334337">Mathematics with Applications</a>") for the course is supposedly incredibly hard to follow. I'm a big fan of easy-to-read literature, with lots of thorough examples and test questions; but I admit, the reviews about this text sound like it contains anything but.<br>
<br>
Here is a gist of what we will cover: linear equations, exponential functions, matrices, system of functions, probability, compound interest.<br>
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It's a little early, but I'd like to get my hands on a textbook/resource to make me familiar with some of these concepts before I start the actual class. Is there an introductory algebra book that you liked, and would recommend?tag:ask.metafilter.com,2012:site.226347Tue, 09 Oct 2012 19:33:41 -0800raintreeHelp her learn Alg II by Tuesday
http://ask.metafilter.com/223432/Help%2Dher%2Dlearn%2DAlg%2DII%2Dby%2DTuesday
Sister just learned she has to take an Algebra II test on Tuesday that covers the whole shebang. She's forgotten (repressed?) most of it. What's her best bet for an Algebra II crash course that will go over all the topics? She's very smart, but not a math person.tag:ask.metafilter.com,2012:site.223432Thu, 30 Aug 2012 10:04:47 -0800goosechasingMy Trig Teachers Name Was Mr. Angle But That Didn't Make Him A Good Teacher.
http://ask.metafilter.com/222158/My%2DTrig%2DTeachers%2DName%2DWas%2DMr%2DAngle%2DBut%2DThat%2DDidnt%2DMake%2DHim%2DA%2DGood%2DTeacher
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. Due to some amazingly awful teachers at some key points in my life Math and I have been in a state of cold war for decades. I'd really like for that not to be the case any more.<br>
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Ideally I'm looking for something like <a href="http://projecteuler.net/index.php">Project Euler</a> or <a href="http://rubykoans.com/">Ruby Koans</a> are for programming. That is: A site with increasingly difficult concrete problems that need solving, not just naked formulae. Substantially prefer hands on/reading over watching videos/lectures (<a href="http://www.khanacademy.org/">Khan Academy</a> hasn't really resonated with me).<br>
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As I mentioned pretty much any branch of math is fine. Algebra, trigonometry, calculus, differential equations, statistics, you name it, I'd like to be better at it.<br>
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High school level and above.tag:ask.metafilter.com,2012:site.222158Mon, 13 Aug 2012 12:20:53 -0800OokseerMath is Hard (I need help)
http://ask.metafilter.com/220566/Math%2Dis%2DHard%2DI%2Dneed%2Dhelp
Math is hard. Please help me with a slope-related problem. I have a project that is 103 inches high on one end, and 119 inches high on the other end. It is 394 inches long.<br>
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Given this information, I need an on-line calculator that can tell me the height of a vertical line drawn at any point along the 394 inch length.<br>
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PS: I know this is probably simple math, but I'm utterly failing at this for hours and hours. If I have to do the actual math problem I will, but I feel at this point that some kind of automatic calculator is going to be the best solution to get me the <i>right</i> answers, especially since I'm going to need to calculate 20 (or more) vertical lines along this distance.<br>
<br>
Thank you!tag:ask.metafilter.com,2012:site.220566Sun, 22 Jul 2012 15:49:52 -0800anastasiavIs it possible to solve for X?
http://ask.metafilter.com/213821/Is%2Dit%2Dpossible%2Dto%2Dsolve%2Dfor%2DX
<strong>(Y)(S^N) = (M)(X^(N+E)) - (Y)(X^N)</strong> Is it possible to solve for X? I'm working on a manuscript (psychophysics), and it would be nice if I could solve for X in the following equation:<br>
<br>
(Y)(S^N) = (M)(X^(N+E)) - (Y)(X^N)<strong><br>
</strong><br>
the damn E term seems to be ruining things. Without it, it's simple enough.<br>
<br>
My math isn't the greatest, so I could really use some help!<br>
<br>
thanks!tag:ask.metafilter.com,2012:site.213821Wed, 25 Apr 2012 14:45:27 -0800spacediverMr. Math Monster, I presume?
http://ask.metafilter.com/211266/Mr%2DMath%2DMonster%2DI%2Dpresume
Help me to learn math as an adult when I still despise the frustrating beast from my childhood! Since I was a kid, I’ve always struggled with math. I was apparently very good at it when I was a little girl, grasping concepts that hadn’t been taught to me yet, but somewhere in there I determined I hated math. Or that it was too hard. I even drew up a manifestation of my fear, the Math Monster. With 7’s for spines, 6’s for claws, 5’s for teeth, and extra numbers floating about in its half gelatinous, half dragon form, the creature is STILL what I think of when I even halfway glimpse an equation with x = ?.<br>
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Now, several years and maybe 2 to 3 college level Algebra classes later, I’m an adult who’s realized that math is actually useful. And pretty much a requirement for life. Especially when my “maybe I could…” interests show me possible life paths involving chemistry, physics, quadratic equations, and theoretical computer science.<br>
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Look, I know I’m smart, but I just need things explained to me in a way I can visualize. I’ve grasped many algebraic concepts before, but I find it difficult to remember even a few months later how to, let’s say for example, find the percentage for a restaurant tip.<br>
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Basically, I’m trying to get back into the math groove, and I’m looking for recommendations on textbooks that are neither dull as shit nor pandering like a kid’s picture book. I just want math to be interesting to me. These textbooks should also obviously be as accurate as possible, since I wouldn’t know an error even if it threw me a wet t-shirt party. <br>
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I note, btw, that I never was able to memorize my multiplication tables and have therefore become a near advanced level wizard at finger tapping to half sing-song tricks such as “5 x 5 = 25, 5 x 6 = THIR-ty” and “9 x 9 = the 49er’s” which flit by so fast now, I barely notice them anymore.<br>
Also of possible importance: if geometry were the only mathematical subject of importance, I’d have _that_ beast paraded around on a leash, wearing a tag that says “Snuffles”.<br>
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SO! More or less I want to review math starting from Algebra, reviewing Geometry, and onward. Can you help?tag:ask.metafilter.com,2012:site.211266Sat, 24 Mar 2012 04:33:38 -0800DisreputableDogOnline mathematics
http://ask.metafilter.com/208575/Online%2Dmathematics
Which are the best online courses for studying algebra and progressing up to trig, calculus, and differentials? Should I look into places like Khan Academy, MIT Open Courseware, etc? Does a community like Reddit have study groups? What other places should I look and and why? Quality is more important than whether it's free or cheap, and it needs to be something I can do strictly at home. I'd also like to know who offers options for tutoring, grading, assistance, etc. I'm pretty self-motivated and have reasons to learn this stuff.. I just need to know where to go.tag:ask.metafilter.com,2012:site.208575Sun, 19 Feb 2012 08:39:08 -0800crapmaticSimple solution
http://ask.metafilter.com/204944/Simple%2Dsolution
This is pretty straightforward algebra/chemistry which is why I'm embarrassed to ask my co-workers to help me so... If I have the dilution ranges of a series of solutions of MSG, how can I figure out, in grams, how much MSG I need in 1L of water to make the stock solution? I get that:<br>
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x M =y moles/z L <br>
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Let's say my stock would be 1.0x10(-1)M. And the molar mass of MSG is 169.111g/mol. <br>
<br>
Given the above:<br>
<br>
0.1M (msg) = 0.1moles/1.0 liter <br>
<br>
and converting moles to grams = 0.1 moles x 169.111g/mol = 16.9g of MSG/L<br>
<br>
Is that it? Or did I miss some element? It seems too simple but it's been a while.tag:ask.metafilter.com,2012:site.204944Thu, 05 Jan 2012 12:25:38 -0800KatineI still KNOW the quadratic equation, just not what it means
http://ask.metafilter.com/198850/I%2Dstill%2DKNOW%2Dthe%2Dquadratic%2Dequation%2Djust%2Dnot%2Dwhat%2Dit%2Dmeans
I have forgotten basically all of math, and I want to learn it again from the ground up. While attempting to prep for the GRE, I realized that I have really lost my entire math background. I was extremely frustrated by trying to do the exercises in my GRE book, because I've forgotten even the little things from, like, 7th grade algebra that I used to take for granted I knew.<br>
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The thing is, I actually used to be pretty good at math- I did two years of AP Calculus in high school and did, well, ok at it- but I then placed out of college math with my AP scores and never did math again. Now it's been five or six years and I can't so much as add fractions or remember what the purpose of the quadratic equation is. I couldn't even remember the formula for the diameter of a circle until I looked it up, for cripe's sake.<br>
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This isn't just about prepping for the GRE. As I was struggling with my GRE book, I realized that I actually LIKED math, and I'm sad that I've forgotten it. It's like I forgot a language I used to know, or something. (I <em>thought</em> I didn't like it while I was in school, but that was mostly because I had an hour of math class and an hour of math homework every single day, which burned me out.)<br>
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SO. I would like to completely reboot my math knowledge, starting with the absolute most basic stuff (like, arithmetic basic) and moving up at my own pace until I can do at least basic calculus again. Ideally I would have access to LOTS of problems with available answers, so that I could spend as much time as I needed on a particular topic. I expect I'll advance through the basic stuff pretty speedily, and then take my time with the more advanced stuff. <br>
<br>
What is the best resource or resources for this? And have any of you guys ever tried to do this before, after such a gap? How was it?tag:ask.metafilter.com,2011:site.198850Wed, 19 Oct 2011 08:37:15 -0800showbiz_liz1 + 10 + 100 + ... = -1/9
http://ask.metafilter.com/191843/1%2D10%2D100%2D19
Mathfilter: In Gelfand's exceptional <a href="http://www.amazon.com/exec/obidos/ASIN/0817636773/metafilter-20/ref=nosim/">Algebra</a> text, he is talking about the formula 1 + x + x^2 + x^3 + ... = 1/(1 - x). He uses the Achilles racing the tortoise model when first introducing the formula. He discusses the case x = 10, whence 1 + 10 + 100 + 1000 + ... = -1/9. Then he says the following: "Is it possible to give a reasonable interpretation of the (absurd) statement 'Achilles will meet the turtle after running -1/9 meters?' (Hint: Yes, it is.) " <br>
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I have puzzled over this for awhile and am not sure what he had in mind. Does the hive mind have any ideas?tag:ask.metafilter.com,2011:site.191843Wed, 27 Jul 2011 06:45:57 -0800wittgensteinLinear Relationships in Real Life?
http://ask.metafilter.com/191311/Linear%2DRelationships%2Din%2DReal%2DLife
I am redesigning a high-school Algebra course so as to make it more meaningful to the students. To that extent, I am trying to gather as many examples throughout our world of linear relationships. I was hoping to tap into the collective wisdom of this group to come up with as long a list as possible of linear relationships that actually exist (not contrived stuff). I once knew a teacher who had a plant that grew at a linear rate. I don't know the type of plant, however. And there are so many other linear relationships around us. I don't want everything they see be about a car's distance from home or the amount of money they saved. What do you know of that exhibits a linear relationship? I'd love to have a long list for students so that they see that studying linear relationships in Algebra really does matter. Thanks for any help in making this course more worth while to the students!tag:ask.metafilter.com,2011:site.191311Thu, 21 Jul 2011 05:06:40 -0800mathmattersIf an geeky child is traveling South at 839 MPH, and his nerdy dad is going North at...
http://ask.metafilter.com/187878/If%2Dan%2Dgeeky%2Dchild%2Dis%2Dtraveling%2DSouth%2Dat%2D839%2DMPH%2Dand%2Dhis%2Dnerdy%2Ddad%2Dis%2Dgoing%2DNorth%2Dat
My son, who is finishing up third grade, loves math and especially the basic Algebra he's been doing. He is actually sad to be leaving school for the summer because he's so into it. How can I keep this going for him over the summer? Fun books, board games, computer (on-line and OSX) games? Seriously, Jason Fox is this kid's idol. He desperately wants to learn Calculus, though I don't think he even knows what that is. For now he's happy doing algebra such as "2x + 5 = -7 + 10x" (Those are just random letters and numbers. I have not checked if that's a legit equation. I spent my summers avoiding math, you see)<br>
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He's finishing up 3rd grade at a Montessori school, ready to go into forth, or "Upper El" as they call it. While I want him to have the usual summer of playing Minecraft, chucking rocks at beehives, and frolicking merrily outside I'd like to keep him entertained with whatever math he's willing to do.<br>
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So what can I give him? While computer games are fun I would prefer non-computer things if they exist. Interesting books (not just books of random problems), board games, TV-shows, YouTube videos, activities, etc. I'm happy to know about any computer games as well. We're Mac people, at least at home. Really anything that will engage him and help him to <em>understand</em> the math he's doing.<br>
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He is a nine year old, and while he's advanced in math for his age he is still a kid, so anything should be somewhat age appropriate.<br>
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Everything I give him will be optional for him over the summer, of course. I'm not interested in pushing him where he doesn't want to go.tag:ask.metafilter.com,2011:site.187878Wed, 08 Jun 2011 10:43:33 -0800bondcliff