Leave these fields empty (spam trap):
Name
You can leave this blank to post anonymously, or you can create a Tripcode by using the format Name#Password
A subject is required when posting a new thread
Subject
Comment
[*]Italic Text[/*]
[**]Bold Text[/**]
[~]Taimapedia Article[/~]
[%]Spoiler Text[/%]
>Highlight/Quote Text
[pre]Preformatted & Monospace text[/pre]
1. Numbered lists become ordered lists
* Bulleted lists become unordered lists
File

Sandwich


Math Puazzle by Edward Clayfoot - Wed, 07 Mar 2012 15:26:00 EST ID:WGpLpasI No.7647 Ignore Report Reply Quick Reply
1331151960960.jpg -(110259 B, 503x1739) Thumbnail displayed, click image for full size. 110259
So this image just came up on 9gag while I was browsing. I was looking at it for a little bit but haven't found a flaw yet. You guys want to take a look at it?
>>
Shitting Hibberpedge - Wed, 07 Mar 2012 15:52:01 EST ID:HkD41ZO3 No.7648 Ignore Report Quick Reply
the blue and red slopes are not at the same angle, the bottom figure has just a little hole in the middle left because of this.
>>
Shitting Hibberpedge - Wed, 07 Mar 2012 15:52:45 EST ID:HkD41ZO3 No.7649 Ignore Report Quick Reply
>>7648
Oh and the green and orange ones as well
>>
Computer - Sat, 10 Mar 2012 19:58:47 EST ID:quInMO2x No.7671 Ignore Report Quick Reply
leave it to 9gag to be tricked by an 8 year old meme.
>>
Oliver Gevingwater - Sat, 10 Mar 2012 20:07:34 EST ID:gMchC3rx No.7672 Ignore Report Quick Reply
I almost feel we could make a calendar out of /math/ based on how regularly this gets posted.
>>
Basil Dunningbury - Sun, 11 Mar 2012 10:55:47 EST ID:1cjOVslP No.7684 Ignore Report Quick Reply
>>7671


link for that russian website with the shit ton of free ebooks and by Edward Pagglechat - Thu, 08 Mar 2012 07:21:35 EST ID:X0/jKuSJ No.7656 Ignore Report Reply Quick Reply
also does anyone have an ebook version of Calculus of one variable by Joseph W. Kitchen? (Publisher: Addison-Wesley (January 1, 1968)).
>>
Frederick Smalllock - Thu, 08 Mar 2012 23:21:24 EST ID:q+PhERO9 No.7664 Ignore Report Quick Reply
library.nu is no longer with us :(
>>
Sophie Bunforth - Fri, 09 Mar 2012 03:13:51 EST ID:X0/jKuSJ No.7665 Ignore Report Quick Reply
>>7664
AW FUCK


Related Rates by Edward Crindernutch - Tue, 06 Mar 2012 20:21:52 EST ID:ow/rlh8l No.7639 Ignore Report Reply Quick Reply
Hey /math/, Calc 1 student here.

So far, I've been pretty good with most of the material. Although I haven't scored quite as high on the tests as I would have liked to.

Last class we started related rates problems. Most of the exercises in the book I don't find a lot of difficulty with, but a number of the harder related rates problems my teacher puts in the notes I find very challenging.

Is this generally considered a difficult portion of Calc 1 courses, or am I just going full retard here?
1 posts omitted. Click Reply to view.
>>
Molly Fobberbit - Wed, 07 Mar 2012 23:53:41 EST ID:XHAestca No.7653 Ignore Report Quick Reply
>Is this generally considered a difficult portion of Calc 1 courses, or am I just going full retard here?

Completely depends on your ability to interpret questions and solve problems. I find them terribly easy but I know a lot of people that don't.
>>
Charles Ganderlock - Thu, 08 Mar 2012 00:26:47 EST ID:zj4pWrXX No.7654 Ignore Report Quick Reply
if you understand derivatives well, and are a good problem solver, then they should come pretty easily to you (at least with some practice).

I recommend doing as many of them as possible. Not really recommending quantity over quality here; work through each problem, understand the necessary steps (relate the variables, find necessary equations, solve for needed derivatives, etc.) but working through more problems helps you recognize patterns within different problems etc. i dont need to harp on dis' shit ya'll.
>>
Wesley Paffingbanks - Thu, 08 Mar 2012 00:42:08 EST ID:ow/rlh8l No.7655 Ignore Report Quick Reply
>>7654
I certainly agree with practice.

I'll post a few examples of the level of difficulty my instructor expects of us.
The problems in the text are far to easy. Math for me isn't like chemistry or biology where once I understand the concepts I can quite well.

Mathematics takes that extra step of understanding...and lots of practice. At least for me.
>>
Charlotte Nummlewurk - Thu, 08 Mar 2012 08:29:38 EST ID:Y7EfoA8L No.7657 Ignore Report Quick Reply
related rates were the hardest part of calc 1 for me. instead of slamming your head against a wall, just look up solutions to lots of problems and see the method. then just do a few problems until you get it.
>>
Molly Gackledock - Thu, 08 Mar 2012 17:20:39 EST ID:BgRBA1g7 No.7659 Ignore Report Quick Reply
I found related rates to be my saving grace. Until then I could do the math, and I understood it could solve some problems but it didn't seem like I was solving real world problems. When I saw a problem involving like the fuel level of a rocket while its traveling, or the acceleration ( x mass) to get the force required to propel something, I started to realize it really is pretty useful. For me, the physics connection really makes it click, but I love physics so...


What is a derivative ? by Jenny Wocklefoot - Mon, 05 Mar 2012 11:17:27 EST ID:LFUhSvVn No.7617 Ignore Report Reply Quick Reply
1330964247748.jpg -(32852 B, 346x346) Thumbnail displayed, click image for full size. 32852
So I'm in school and all that jazz and I am doing fine, but I don't really get what a derivative is. I have vague imaginations in my head about it but I don't really ''know what it is''.
If we derive a function, for example f(x) = 5x^3 + 2x^2 + x we get f '(x) = 15x^2 + 4x +1

What exactly is the derivative of that function.
>>
Nigger Blackridge - Mon, 05 Mar 2012 12:07:19 EST ID:l1meLf61 No.7618 Ignore Report Quick Reply
>>7617
It is the rate of change with respect to the variable x in that case. An easy way to think about it is that the derivative gives the slope of the function. So f'(x) tells you the value of the slope on a graph y=f(x).
>>
Basil Debblelock - Mon, 05 Mar 2012 12:33:35 EST ID:yIvUAryG No.7619 Ignore Report Quick Reply
Think of the graph of f(x) = x^2. (let's consider the positive-x side for simplicity). The y-values increase as you go along x, but the rate of the increase grows as well. From the rules you probably already know, the derivative is f '(x)=2x. That's the function that represents the rate of change of f(x) = x^2.

Now imagine the graph of f(x)=2x. It's a straight line. It increases, but the rate at which it increases is constant. The derivative of that would be f '(x)=2.

Now think of the graph f(x)=2. It's a flat line. It's not increasing. It's derivative is 0.

Like the above guy said an easy way to think about it is: the derivative gives the slope of the function you're deriving. It's like slope in function form. You can have a general formula f '(x), and you can use it to plug in a point to find the slope (rate of change) at that particular point.

So what's the rate of change of f(x) = 5x^3 + 2x^2 + x @ x=3? Just calculate that f '(x) = 15x^2 + 4x + 1, and plug in the x-value you want to know about.

You can even go on to higher-order derivatives, which is like "the rate of change of the rate of change". Or f ''(x), f ''(x).

Has your prof. confused you with the whole dy/dx notation yet? It's all related.
>>
Fanny Miggletene - Mon, 05 Mar 2012 12:44:39 EST ID:XLQ0N+7N No.7620 Ignore Report Quick Reply
>>7618
Geometrically speaking a derivative is the slope of a line tangent to the function at any point along the function. Mathematically speaking it is the rate of change of some value with respect to the variable you are deriving by, and in terms of how it is taught it is the slope between two points infinitesimally close together both on the same function.
>>
Jenny Wocklefoot - Mon, 05 Mar 2012 13:10:16 EST ID:LFUhSvVn No.7621 Ignore Report Quick Reply
It's crystal clear now, thanks guys.
>>
Betsy Billingwater - Tue, 06 Mar 2012 00:32:36 EST ID:wAa7qP9r No.7628 Ignore Report Quick Reply
Make f(x) the miles your car has traveled after x hours
f'(x) is the speedometer, or better, a function to find where the speedometer would be at any place x.

For starters lets take f(x) = 60x. So back in the analogy we're gaining sixty miles for every hour. The derivative would be f'(x) = 60 because the speedometer would always be at sixty.

Alright, let's forget the analogy now. Let's use the normal math terms.
What about f(x) = x^2 ? A quick way to check derivatives is to find the slope between two points. How do we do this?

f(x,2) - f(x,1)
---------------
x,2 - x,1

Where x,2 is a place after x,1, get them as close as you can, but know there's always closer (a infinitive limit)

Apply this to our problem of x^2 (1.1^2 -1^1)/(1.1 - 1) = 2.1 (2.1^2 -2^2)/(2.1 - 2) = 4.1
Comment too long. Click here to view the full text.


Linear Algebra by Jenny Seppertut - Sun, 04 Mar 2012 21:59:54 EST ID:YDu+jK6j No.7603 Ignore Report Reply Quick Reply
1330916394896.png -(5938 B, 281x114) Thumbnail displayed, click image for full size. 5938
I would very much appreciate if someone could point me in the right direction with this
>>
Fuck Gindlekudging - Mon, 05 Mar 2012 00:36:07 EST ID:q+PhERO9 No.7612 Ignore Report Quick Reply
1330925767953.gif -(975230 B, 499x299) Thumbnail displayed, click image for full size. 975230
http://en.wikipedia.org/wiki/Diagonalizable_matrix#Diagonalization
>>
Basil Debblelock - Mon, 05 Mar 2012 09:05:57 EST ID:yIvUAryG No.7616 Ignore Report Quick Reply
hmm is there a way to do this without eigenvectors or eigenvalues
>>
Fuck Gindlekudging - Mon, 05 Mar 2012 16:47:16 EST ID:q+PhERO9 No.7622 Ignore Report Quick Reply
Well, I can't remember any other ways to do it and looking here: http://en.wikipedia.org/wiki/Matrix_decomposition
Eigen decomposition is the only one with the form you want so I think you're stuck


Need help with this by Cedric Fugglebetch - Sat, 25 Feb 2012 13:10:09 EST ID:+3F/Z4RC No.7494 Ignore Report Reply Quick Reply
1330193409922.png -(743513 B, 1600x1200) Thumbnail displayed, click image for full size. 743513
I'm at my wits end I have no idea how to go about this.

You need to store the integer 5857458489 on a computer that cannot store any numbers larger than 100 and you need to do arithmetic calculations with the 10 digit number. Noting that 2*3*5*7*11*13*17*19*23*29 = 6469693230>5857458478. Use the chinese remainder theorem to store 5857458489 that will enable you to do calculations with the 10 digit number. Then use the design to store the outcome 5857458489 - 4927100893
>>
Phoebe Musslefedging - Mon, 27 Feb 2012 02:48:40 EST ID:rktf4e7v No.7516 Ignore Report Quick Reply
>>7494

First, think about storing the number 5857458489 using the CRT. This can be done by simply storing the residues modulo the primes below 27 (or whatever upper limit you need, this will depend on the size if the number to store).
>>
Phoebe Musslefedging - Mon, 27 Feb 2012 03:20:48 EST ID:rktf4e7v No.7517 Ignore Report Quick Reply
>>7516

this should give you something like:
1, 0, 4, 1, 3, 12, 12, 17, 5, 6

Now do the same for the second number. Then find the difference between each corresponding residue. And finally use the differences to reconstruct the new value (the answer to the difference question).
>>
probably in your class - Mon, 05 Mar 2012 02:59:28 EST ID:qxVF1jNJ No.7614 Ignore Report Quick Reply
man, legit, this professor is whack. expects us all to be geniuses to know how to solve half of what's on here...


Probability Density Function by Hamilton Dindleshit - Sun, 04 Mar 2012 22:28:34 EST ID:3CdfSPjz No.7606 Ignore Report Reply Quick Reply
1330918114859.gif -(4732 B, 440x335) Thumbnail displayed, click image for full size. 4732
If I have a set of data (stream flow measurements), how do I create a probability density function for it?
>>
Fuck Gindlekudging - Mon, 05 Mar 2012 00:34:04 EST ID:q+PhERO9 No.7611 Ignore Report Quick Reply
for each observation / bucket:
# of that one seen / total number

so if i have a bunch of measurements { 1, 2, 3, 4, 1, 1, 3, 1, 3, 2}

1s: 0.4
2s: 0.2
3s: 0.3
4s: 0.1

x
x _ x
x x x
x x x x
1 2 34


Calculus resources? by Hamilton Drundlestane - Sun, 04 Mar 2012 22:07:02 EST ID:Uws6cFtU No.7604 Ignore Report Reply Quick Reply
Hey /math/ looking for good calculus resources (aside from Khan and Patrick jmt..already watched).

I remember someone posting a link to their professors page with notes and practice problems and stuff, that would be nice.

Or, just a good text book.

I'm currently using "Calculus, by Rogawski" and it isn't that great. Concepts are explained with many steps skipped and answer book has lazy, often incorrect, solutions.
>>
Jenny Seppertut - Sun, 04 Mar 2012 22:10:29 EST ID:YDu+jK6j No.7605 Ignore Report Quick Reply
>I remember someone posting a link to their professors page with notes and practice problems and stuff, that would be nice.
This guy has great notes. They definitely helped me get dat A in Calc 2. I wish I found it earlier
http://tutorial.math.lamar.edu/


How does I math? by Frederick Shittingbury - Mon, 27 Feb 2012 23:46:00 EST ID:q1+uR/JW No.7529 Ignore Report Reply Quick Reply
1330404360910.gif -(277818 B, 255x198) Thumbnail displayed, click image for full size. 277818
Im a pretty intelligent guy, but math has always been a major weak-point. I attribute this to a long string of shitty math "teachers" during my religious schooling.

Well I want to rectify that. Ive recently started on two books. "Introduction to Logic" by Irving Copi and Godel Escher Bach. Any other suggestions for improving my math skills?
12 posts omitted. Click Reply to view.
>>
Sidney Tootshit - Fri, 02 Mar 2012 12:19:58 EST ID:q9MtF4bO No.7567 Ignore Report Quick Reply
Khan Academy is useless. Math is about doing, not watching. Download Sullivans algebra books and work through em.
>>
Walter Fockleforth - Fri, 02 Mar 2012 22:17:26 EST ID:+V3CPwdO No.7576 Ignore Report Quick Reply
>>7567
It's by no means useless. You won't master any material by watching the videos alone, but if you watch them before and/or after a lecture covering the same material and do the problems in your book you should be doing just fine.
>>
Sophie Dackleworth - Sun, 04 Mar 2012 17:03:21 EST ID:bahXJ0OQ No.7602 Ignore Report Quick Reply
>>7558
Khan Academy is best after attending and paying attention in class. The guy who does the videos does a great job at slowing and breaking the whole thing down to it's most basic parts, something most professors don't really do.

It's great for figuring out why you have to manipulate that variable that way or why you have to use this equation to solve that problem.
>>
Hugh Pickcocke - Sun, 04 Mar 2012 23:19:58 EST ID:xKqkWkgS No.7607 Ignore Report Quick Reply
Read letters to a young mathematician, by ian stewart. Look up math topics on wikipedia and see what interests you.
>>
Hugh Pickcocke - Sun, 04 Mar 2012 23:33:16 EST ID:xKqkWkgS No.7610 Ignore Report Quick Reply
>>7555
Then google it, dumbass


Tell me the meaning of life. by Walter Blommerlock - Fri, 02 Mar 2012 17:57:38 EST ID:MFahwZy7 No.7571 Ignore Report Reply Quick Reply
1330729058249.jpg -(28876 B, 350x291) Thumbnail displayed, click image for full size. 28876
my bredren

let me tell you what life is about

SKRILLEX
GRAPHCALC.EXE
MARIJUANA

And a damn ice cold glass of water.
>>
Ebenezer Hedgebedging - Sat, 03 Mar 2012 11:27:51 EST ID:ny+Jmrrr No.7584 Ignore Report Quick Reply
I want to fondle those tits.
>>
Ebenezer Blettingkot - Sat, 03 Mar 2012 13:07:58 EST ID:Y7EfoA8L No.7586 Ignore Report Quick Reply
1330798078786.jpg -(46687 B, 480x480) Thumbnail displayed, click image for full size. 46687
DICKS EVERYWHERE
>>
Whitey Sattingwill - Sat, 03 Mar 2012 15:21:32 EST ID:O0do/Mst No.7587 Ignore Report Quick Reply
What is your reasoning for believing that life is "about" a shitty American electronic DJ , some random graphing utility, a South Asian plant, and a single glass of H20? You better pony up a proof and some definitions if you expect this bullshit to fly.

The meaning of life, or what we do on a basic level, is simply to survive and reproduce. Although all the trappings of human society are nice, but we cannot justify how any part of it is the purpose of or necessary for our existence.
>>
Shitting Sissleham - Sun, 04 Mar 2012 16:02:33 EST ID:pnmxrNot No.7600 Ignore Report Quick Reply
>>7587
You sir are awesome
>>
Hugh Pickcocke - Sun, 04 Mar 2012 23:29:50 EST ID:xKqkWkgS No.7609 Ignore Report Quick Reply
>>7587
>he thinks the meaning of life isn't math
sorry, but you only get a cookie if you say the right answer


Simple prolem by Westy McEastcoast - Fri, 02 Mar 2012 05:24:27 EST ID:CoZrV5u2 No.7565 Ignore Report Reply Quick Reply
1330683867768.png -(148914 B, 546x500) Thumbnail displayed, click image for full size. 148914
While following a calculus lecture, the following is presented as a first derivative and I cannot get it. Help is appreciated.
>>
Eugene Hendersog - Fri, 02 Mar 2012 12:15:42 EST ID:BgRBA1g7 No.7566 Ignore Report Quick Reply
Your answer is correct. I'm not exactly sure what form of factoring or manipulating they did to get that answer but I'm guessing they must be equivalent.
>>
Sophie Sedgekark - Fri, 02 Mar 2012 13:29:14 EST ID:dDockSii No.7568 Ignore Report Quick Reply
(x-5)^3 *[(x-5)+4x)]
(x-5)^3 *[(5x-5)]
(x-5)^3*5(x-1)
5(x-5)^3(x-1)
>>
Westy McEastcoast - Fri, 02 Mar 2012 14:15:11 EST ID:CoZrV5u2 No.7569 Ignore Report Quick Reply
>>7568
Thanks to you both. It was late and I was getting frustrated.
>>
Edwin Pickfield - Fri, 02 Mar 2012 14:32:54 EST ID:ZhzReTvI No.7570 Ignore Report Quick Reply
Something one of my cal profs told me not to worry too much about the answers provided in the book as the questions and answers are all written by grad students so they like to provide needlessly obtuse answers.
>>
Fanny Dattingwell - Sun, 04 Mar 2012 15:54:07 EST ID:T24UCYN6 No.7599 Ignore Report Quick Reply
The product rule and the chain rule.

y = x(x -5)^4

Affectionately memorized: the derivative of the first times the second, plus the first times the derivative of the second

y' = (1)(x - 5)^4 + x(4)(x - 5)^3(1)
y' = (x -5)^4 + 4x(x - 5)^3 factor out the (x - 5)^3
y' = (x - 5)^3 ((x - 5) + 4x)
y' =(x -5)^3(5x - 5) you can factor the 5 out of here
y' = (x -5)^3 * 5(x - 1)

or, rewritten in the form they have,

y' = 5(x - 5)^4(x-1)


quadratic equation by William Wommlesot - Sat, 03 Mar 2012 18:31:53 EST ID:BDCqNZ4o No.7591 Ignore Report Reply Quick Reply
1330817513901.jpg -(23694 B, 1031x434) Thumbnail displayed, click image for full size. 23694
consider the following quadratic equation: using the standard form ax'squared'+bx+c=0 of the quadratic equation in the pic.
factor the left hand side of the equation into two linear factors. enter the appropriate factors.
>>
Hamilton Sankinlock - Sat, 03 Mar 2012 21:54:18 EST ID:HYMWaN9y No.7592 Ignore Report Quick Reply
couldn't you square root both sides and be left with 7x=5. Then simplify that down to x=5/7.
>>
Hamilton Sankinlock - Sat, 03 Mar 2012 22:00:02 EST ID:HYMWaN9y No.7594 Ignore Report Quick Reply
>>7592
I meant + or - 5/7
>>
Augustus Worthingcocke - Sun, 04 Mar 2012 15:53:46 EST ID:XHAestca No.7598 Ignore Report Quick Reply
  • 5/7, + 5/7



<<Last Pages Next>>
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
Report Post
Reason
Note
Please be descriptive with report notes,
this helps staff resolve issues quicker.