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have I discovered this? by Isabella Surrylodge - Fri, 27 Jun 2014 02:59:35 EST ID:ySRm4RKM No.14133 Ignore Report Reply Quick Reply
File: 1403852375276.gif -(6586B / 6.43KB, 644x177) Thumbnail displayed, click image for full size. 6586
DICKS EVERYWHERE
>>
David Sibbledure - Fri, 27 Jun 2014 13:18:40 EST ID:p8Vzq3fC No.14136 Ignore Report Quick Reply
Discovered what?
>>
Nigger Winkinpat - Sat, 05 Jul 2014 17:44:54 EST ID:Dn4zhXKX No.14171 Ignore Report Quick Reply
>>14133
Probably. You can call it Surrylodge's Lemma. Although if your proof is computer assisted, it might be controversial.


OK math lets count by Beatrice Trotwater - Sat, 24 May 2014 17:18:16 EST ID:Le9Cy2Bo No.14031 Ignore Report Reply Quick Reply
File: 1400966296303.jpg -(43371B / 42.35KB, 646x430) Thumbnail displayed, click image for full size. 43371
one!
11 posts and 3 images omitted. Click Reply to view.
>>
Nicholas Bablinglock - Sun, 29 Jun 2014 10:57:19 EST ID:KRSGkVa1 No.14140 Ignore Report Quick Reply
BANGARANG
>>
Reuben Pisslefoot - Mon, 30 Jun 2014 19:14:03 EST ID:jkYtMoE5 No.14152 Ignore Report Quick Reply
-1/12
>>
Nigger Smallford - Tue, 01 Jul 2014 19:51:57 EST ID:MTIV7/tU No.14156 Ignore Report Quick Reply
1404258717434.gif -(475632B / 464.48KB, 300x181) Thumbnail displayed, click image for full size.
>>14152
My nigga.

This picture is called fuck numbers.
>>
Betsy Cruzzlelat - Fri, 04 Jul 2014 13:27:06 EST ID:p8Vzq3fC No.14166 Ignore Report Quick Reply
>>14152
for those that don't know https://www.youtube.com/watch?v=w-I6XTVZXww
It's a pretty fantastic video, especially if you watch the one about 1/2-1/2+1/2-1/2...
>>
Phoebe Crarrynat - Fri, 04 Jul 2014 23:27:31 EST ID:yHx/72Ow No.14168 Ignore Report Quick Reply
>>14166

not this again...

The sum of the natural numbers is NOT -1/12, this is part of something called Ramanujan summation where you *ASSIGN* values to divergent series so that you can deal with them concretely. It does not mean that if you added all the natural numbers you would get -1/12, that is troll science and the video is completely and totally misleading.

1+2+3+4+... is a divergent series and you cannot add it up to get a negative number, or any number at all for that number. 1-1+1-1+... is not 1/2. Ramanujan is used in the specialized study of infinite series and it is FALSE to say that these things really add up to what is claimed in the video. It really sickens me the way these "educated" people dumb down extremely specialized things to produce something that is completely false in the end. Ugh.


Die math die! by Cyril Bardville - Tue, 01 Jul 2014 20:39:22 EST ID:dZa7zeXl No.14157 Ignore Report Reply Quick Reply
File: 1404261562463.jpg -(145775B / 142.36KB, 900x900) Thumbnail displayed, click image for full size. 145775
Math sucks and this board should die
>>
CrazyFolksTribe !loJSOMZg0g - Wed, 02 Jul 2014 00:26:26 EST ID:8i+nkfnL No.14160 Ignore Report Quick Reply
YOU SHOULD DIE
BITCH


I\neq 1 by Esther Suvingmuck - Sun, 29 Jun 2014 22:33:39 EST ID:3EegWVCd No.14143 Ignore Report Reply Quick Reply
File: 1404095619674.jpg -(24146B / 23.58KB, 500x285) Thumbnail displayed, click image for full size. 24146
On page 39 of Emil Artin's Galois Theory, should the equation

(x^2-x+1)^3-1*x^2(x-1)^2=0

instead read

(x^2-x+1)^3-I*x^2(x-1)^2=0 ?

That confused me a good bit. I just want to be sure I reached the correct conclusion. You can find the book here:
http://projecteuclid.org/euclid.ndml/1175197045
>>
Shit Nocklestirk - Mon, 30 Jun 2014 05:13:11 EST ID:e1p9nP+4 No.14147 Ignore Report Quick Reply
>>14143

Yeah, you're correct. He is showing that that the element x is algebraic over the field k(I) by writing down a specific polynomial that it satisfies. Since the polynomial has degree 6, he obtains the desired bound on the degree of the extension as well.
>>
James Hippersore - Mon, 30 Jun 2014 13:39:41 EST ID:k3j5GQQF No.14148 Ignore Report Quick Reply
>>14147
thanks bro


Math training by James Cubberson - Mon, 16 Jun 2014 18:14:57 EST ID:LFUhSvVn No.14089 Ignore Report Reply Quick Reply
File: 1402956897306.jpg -(81119B / 79.22KB, 634x624) Thumbnail displayed, click image for full size. 81119
I want to be able to solve the problems presented here and similar by the end of the summer, I'm currently at about calculus 2 level engineering math.

How much more do I need to study and what exactly is it that I need to study in order to be able to solve all the problems presented here, I have a lot of time on my hands so I hope my brain is up for it.
>>
Angus Broddleshit - Tue, 17 Jun 2014 21:06:14 EST ID:Dk8yywxc No.14093 Ignore Report Quick Reply
Linear Algebra and Differential Equations, in terms of United States college semesters, normally you would take calculus 3 and then linear algebra and differential equations, so you are two semesters away.

If you go looking around on Amazon or something like that, you should be able to find good textbooks that are readable for independent study for an edge when you take these classes. Personally, I would look for proof based treatments of these subjects to get the most out of it but as an engineering student you may not be required to do much of that. However, if you get a good introductory level linear algebra text for example it should ease you into the proofs and it will help with all your other math classes.
>>
Fanny Podgesick - Wed, 18 Jun 2014 07:07:44 EST ID:LFUhSvVn No.14097 Ignore Report Quick Reply
>>14093
Is #2 a basic linear algebra problem? Or does it already border on functional analysis?
>>
Wesley Supperspear - Sun, 22 Jun 2014 10:28:28 EST ID:8NZnQ0yA No.14112 Ignore Report Quick Reply
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>>14097
The second problem should be provable in a basic linear algebra context since the algebraic structure is just a finite dimensional real vector space without the additional structure that usually allows for functional analysis type study.
>>
Walter Binnerchodge - Thu, 26 Jun 2014 23:26:11 EST ID:HbNSsmiC No.14131 Ignore Report Quick Reply
#3 is an application of mean value and intermediate value theorem from calculus
>>
Shit Nocklestirk - Mon, 30 Jun 2014 03:18:39 EST ID:e1p9nP+4 No.14144 Ignore Report Quick Reply
(1) is single variable calculus.

hint: for the "only if" . assume that both u_n are convergent and the sum is infinite and obtain a contradiction nearly immediately.

the "if" follows from the monotone convergence theorem and the sequence comparison test

(2) is standard linear algebra
hint: diagonalize!!!!!!! eigenvectors are your friend.

(3) is single variable calculus and very simple

hint: see the comment of the person above

(4) is interesting, but doesn't entail and ODE tools or anything
hint: look at Taylor series solutions to the equation to get form a conjecture for the shape of the solutions, then prove conjecture using standard integration techniques. this will be easy for (a) and tricky for (b).


Vector Calc by Rebecca Clobberforth - Sun, 29 Jun 2014 20:48:28 EST ID:wer7kd6a No.14142 Ignore Report Reply Quick Reply
File: 1404089308339.jpg -(134606B / 131.45KB, 1142x297) Thumbnail displayed, click image for full size. 134606
round 3 of trying to type this on a damn forum

Suppose f is any function with continuous second-order partial derivatives such that f(0,0)=0 and (,0) is a critical point of f. Write an expression for the second-degree Taylor polynomial, Q, of f at (0,0)
Q(x,y)=f(a,b)+fx(a,b)(x-a)+fy(a,b)(y-b)+(1/2)fxx(a,b)(x-a)^2+fxy(a,b)(x-a)(y-b)+(1/2)fyy(a,b)(y-b)^2


multiply 0 by Charles Pickman - Sat, 28 Jun 2014 18:22:13 EST ID:tsVlvxIF No.14138 Ignore Report Reply Quick Reply
File: 1403994133366.jpg -(55980B / 54.67KB, 500x383) Thumbnail displayed, click image for full size. 55980
how is it that when you multiply something by 0 the answer is 0? say i have 3 carrots and i multiply the carrots 0 times, would i still have 3 carrots?
>>
Samuel Bluttingham - Sat, 28 Jun 2014 20:05:05 EST ID:8PJ0nVdr No.14139 Ignore Report Quick Reply
http://mathforum.org/library/drmath/sets/select/dm_multiply_zero.html
>>
Bob Bob - Sun, 29 Jun 2014 20:33:18 EST ID:Dk8yywxc No.14141 Ignore Report Quick Reply
>>14138

1*3 = 3 right?

0*3 = (1-1)*3 = 3 - 3 = 0

So you would have 0 carrots.


Sum and diffrences by Phyllis Dringerstore - Thu, 26 Jun 2014 07:28:26 EST ID:aNYGNAvO No.14123 Ignore Report Reply Quick Reply
File: 1403782106366.jpg -(322156B / 314.61KB, 1080x1920) Thumbnail displayed, click image for full size. 322156
Can someone want to help me with c)? I understand it if there are only two parts but i dont know what to do when there are three.
>>
Phyllis Dringerstore - Thu, 26 Jun 2014 07:29:31 EST ID:aNYGNAvO No.14124 Ignore Report Quick Reply
Ops subject was in norwegian
>>
Frederick Punderstet - Thu, 26 Jun 2014 18:26:01 EST ID:lH5+Lnwt No.14125 Ignore Report Quick Reply
Can you give some more context? What are you meant to be doing with them?
>>
Fuck Fellyfoot - Fri, 27 Jun 2014 06:10:08 EST ID:5cShHy72 No.14135 Ignore Report Quick Reply
>>14123
Just apply the rules given in
http://en.wikipedia.org/wiki/Trigonometric_identities#Angle_sum_and_difference_identities
and do the evaluations for Sine and Cosine, as seen in the example.


Squareroots Algebra by Esther Samblechan - Mon, 23 Jun 2014 17:55:42 EST ID:BE8EyBvj No.14115 Ignore Report Reply Quick Reply
File: 1403560542315.jpg -(34751B / 33.94KB, 837x195) Thumbnail displayed, click image for full size. 34751
I'm in calculus and I can't even algebra.
Take a look at this image here. First, I don't understand why they multiplied by (1/x) on top and bottom. I would have never thought to do that to simplify that.

But my main question is in the denominator after it is multiplied by (1/x). What is going on there?!
I thought that if you had a root, like sqrt(1+x), that weren't allowed to go inside and manipulate each term in the root. I thought it was all one part of the root.

Can someone explain the algebra of that highlighted step please?
Thank you
1 posts omitted. Click Reply to view.
>>
DFENS - Tue, 24 Jun 2014 02:50:51 EST ID:S/NbzhXl No.14118 Ignore Report Quick Reply
>>14116
This. Also, you might have not gotten to this point in your calculus course, but when you learn L'Hopitals Rule for evaluating limits this will be easier.
>>
Polly Snodforth - Wed, 25 Jun 2014 15:59:39 EST ID:BE8EyBvj No.14119 Ignore Report Quick Reply
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>>14116
Ah okay. It makes sense on paper. I still would have never thought of doing this algebra during a test, but we'll see what happens.

Can someone also explain step-by-step on how this result as achieved? (in image)
>>
Polly Snodforth - Wed, 25 Jun 2014 16:07:02 EST ID:BE8EyBvj No.14120 Ignore Report Quick Reply
1403726822062.jpg -(6578B / 6.42KB, 263x87) Thumbnail displayed, click image for full size.
>>14115
Another question regarding this. Where does the (1/x) go?
>>
Clara Nickleham - Wed, 25 Jun 2014 17:09:27 EST ID:8NZnQ0yA No.14121 Ignore Report Quick Reply
1403730567754.jpg -(130982B / 127.91KB, 768x1024) Thumbnail displayed, click image for full size.
>>14119
The cube root of three can be written as (3)^(1/3) and likewise the square root of three can be written as (3)^(1/2). Recall that exponential expressions of real numbers have the property that
(a^x)(a^y)=a^(x+y)
so
(3^(1/3))(3^(1/2))=3^(1/2+1/3)=3^(3/6+2/6)=3^(5/6).

>>14120
The limit of 1/x as x approaches infinity is zero. That's why as the limit is evaluated in your picture, the 1/x term disappears. If you graph the function f(x)=1/x, then you can visualize that as x approaches infinity, f approaches zero, i.e. f has a horizontal asymptote at zero both as x approaches infinity and as x approaches negative infinity. Can you figure out where f(x)=1/x has a vertical asymptote? Otherwise you might roughly think of the situation as when dividing a fixed number by numbers that get successively and arbitrarily larger, then the quotient tends to zero.
>>
Polly Snodforth - Wed, 25 Jun 2014 18:04:54 EST ID:BE8EyBvj No.14122 Ignore Report Quick Reply
>>14121
Thanks, I understand now.
It's just tricky to wrap my head around that when evaluating limits. That you're allowed to just remove things from within that expression, but only if it's a limit. Or I guess it's more like plugging in for X. But you're plugging in Infinity, which just means 1/x -> 0... or something.

But yeah, thanks! This board is mighty helpful it is.


Visually Understanding Math by Shit Blangertere - Tue, 17 Jun 2014 06:57:11 EST ID:RLkenDTl No.14091 Ignore Report Reply Quick Reply
File: 1403002631911.jpg -(499955B / 488.24KB, 1200x780) Thumbnail displayed, click image for full size. 499955
Hi guys,

Wondering if anyone could point me to an introductory level book on Math that teaches primarily by showing how to visualise the math so that I can understand HOW it works (as opposed to just memorising the equations/procedures and accepting that they work).

I'm thinking of going Feynman's Lectures atm, but am wondering if there's something better you guys might recommend.

Again, would like it to start at the very basics if possible.

Thanks and Jesus.
>>
Nigger Grimson - Tue, 17 Jun 2014 15:24:42 EST ID:8PJ0nVdr No.14092 Ignore Report Quick Reply
How introductory do you need?
>>
Django Fairfeather - Tue, 17 Jun 2014 21:13:55 EST ID:Dk8yywxc No.14094 Ignore Report Quick Reply
>>14091

Most well received modern textbooks will have lots of diagrams for more visual learners, the question is what level of material you're looking for. Are you looking for enjoyable math that may not be taught in a course or fundamentals like algebra and calculus?

If you're hardcore you could get a good translation of Euclid's elements, that is about as visual as it gets. I don't have a good recommendation at algebra level, but if you're wanting to learn calculus, Kline's "Calculus: an intuitive and physical approach" is good and doesn't make many assumptions about what you know. Everyone has their own pet favorite calc book though so it may not be helpful for you.
>>
David Pittford - Wed, 18 Jun 2014 04:23:54 EST ID:Gw2IN3ba No.14095 Ignore Report Quick Reply
>Feynman's Lectures

Though these do include chapters on mathematics, they are primarily geared toward teaching physics (you probably already know this). I hear great things about them; and from what I know of Feynman, he probably does a decent job of presenting mathematics in an easily comprehensible way. This reminds me that I need to get around to reading them myself.

However well he presents the mathematical topics, the scope will be narrow - focussing on just the mathematics of physics. But maybe that's all you're looking for. It really depends on which fields of mathematics you wish to understand and your current understanding. You said you wanted to start from the basics, so as >>14094 suggested, try reading Euclid's Elements. You also hinted that you are a visual learner, so maybe this is also a good fit:

http://www.amazon.com/Proofs-without-Words-Exercises-Classroom/dp/0883857006

And then there's always the most recommended resource for math self-teaching: Khan Academy. Obligatory link:

https://www.khanacademy.org/

That's all I got. Good luck!


Math Majors by Shitty Fattits - Wed, 26 Mar 2014 23:09:49 EST ID:xgdLZpNp No.13814 Ignore Report Reply Quick Reply
File: 1395889789436.gif -(1915993B / 1.83MB, 200x200) Thumbnail displayed, click image for full size. 1915993
Howdy, /math/ -- Are there any math majors out there? What do you guys have for jobs? I have plans on becoming a math teacher (secondary level), and I was just wondering if people here did something like that.
16 posts and 1 images omitted. Click Reply to view.
>>
Walter Meddlenore - Wed, 23 Apr 2014 03:59:18 EST ID:kQQi+WA1 No.13932 Ignore Report Quick Reply
I was just going to ask about majoring in math.

What are some other options besides becoming an actuarie?
>>13817
what do you invest in?
>>
Molly Fuckingfuck - Sat, 26 Apr 2014 11:31:37 EST ID:0Lu9efHk No.13940 Ignore Report Quick Reply
>What do you guys have for jobs?

Stevedore
>>
James Clingerhood - Wed, 28 May 2014 22:38:51 EST ID:wtjqoUcj No.14049 Ignore Report Quick Reply
>>13932
My best friend is a math major who, out of school, went to work in ophthalmic optics. Though that's definitely not the norm.
>>
Ernest Gabberman - Wed, 04 Jun 2014 20:14:36 EST ID:E77E4OX5 No.14063 Ignore Report Quick Reply
My advice as a phd student in (pure) math: if you want to make money, don't study pure math (do applied, if anything). An undergrad degree doesn't go into much else other than teaching/actuarial work. If you enjoy/love the subject, then by all means go into it. Just know what you're getting into.
>>
Nathaniel Povingbury - Mon, 16 Jun 2014 18:39:01 EST ID:E8Uxy4mH No.14090 Ignore Report Quick Reply
>>14063
That's not what my math teacher says!


Help? by Xenia Ohiya - Sun, 15 Jun 2014 23:53:53 EST ID:BfGCwHN9 No.14086 Ignore Report Reply Quick Reply
File: 1402890833782.jpg -(587875B / 574.10KB, 1600x1200) Thumbnail displayed, click image for full size. 587875
Markdown amount = $8.19; markdown rate = 22%. Find the original price and reduced price.

How do you set this up?
>>
Thomas Sellerford - Mon, 16 Jun 2014 09:25:44 EST ID:HTgVxC+C No.14087 Ignore Report Quick Reply
Think of it this way, the markdown amount is equal to 22% of the original price. So 8.19=.22x, then divide each side by .22 to get x by itself and you'll get about $37.23. If that's the original price, then the reduced price is $8.19 less, so you do 37.23-8.19 and you get about $29.04. Hope this helps!


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