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Impossible system of equations by Ernest Hettingchat - Mon, 10 Jun 2013 00:01:15 EST ID:/YrTbYfy No.11856 Ignore Report Reply Quick Reply
1370836875679.png -(8053 B, 380x212) Thumbnail displayed, click image for full size. 8053
Is this even possible? Well, I know it is, because I know the answer, but I have no idea how to get to it. Any help?
16 posts omitted. Click Reply to view.
>>
samsung galaxy s4 - Wed, 19 Jun 2013 17:30:41 EST ID:xowTq9Jq No.11913 Ignore Report Quick Reply
Impossible system of equations - Mathematics - 420chan samsung galaxy s4 http://www.mddesigncontractor.com/ [url=http://www.mddesigncontractor.com/]samsung galaxy s4[/url]
>>
传奇私服 - Wed, 19 Jun 2013 17:32:17 EST ID:IFS2NFip No.11914 Ignore Report Quick Reply
Impossible system of equations - Mathematics - 420chan 传奇私服 http://www.txingzuo.com/
>>
传奇私服 - Wed, 19 Jun 2013 17:34:11 EST ID:vipiEcX7 No.11915 Ignore Report Quick Reply
Impossible system of equations - Mathematics - 420chan 传奇私服 http://www.txingzuo.com/ [url=http://www.txingzuo.com/]传奇私服[/url]
>>
Samsung Galaxy S4 - Wed, 19 Jun 2013 17:43:05 EST ID:vipiEcX7 No.11916 Ignore Report Quick Reply
Impossible system of equations - Mathematics - 420chan Samsung Galaxy S4 http://www.mddesigncontractor.com/ [url=http://www.mddesigncontractor.com/]Samsung Galaxy S4[/url]
>>
Shit Bunstone - Wed, 19 Jun 2013 17:54:28 EST ID:peKcr4s1 No.11917 Ignore Report Quick Reply
1371678868317.jpg -(4952 B, 200x198) Thumbnail displayed, click image for full size. 4952
God damn I hate spambots


Stupid Math Philosophy Bullshit by Nathaniel Snodridge - Wed, 12 Jun 2013 00:35:01 EST ID:CmISY9b9 No.11874 Ignore Report Reply Quick Reply
1371011701837.png -(404532 B, 868x477) Thumbnail displayed, click image for full size. 404532
Do Godel's unprovably true numbers invalidate Russell's Teapot?
>>
Frederick Drombledale - Sun, 16 Jun 2013 21:26:13 EST ID:EJ6Occze No.11893 Ignore Report Quick Reply
No. If you can't prove something then you have no reason to believe it.

Say there are facts you can't prove are true but are true nonetheless. That doesn't give you reason to believe these facts since you don't know whether they are true.
>>
Frederick Drombleshaw - Wed, 19 Jun 2013 17:09:12 EST ID:uvihomwk No.11904 Ignore Report Quick Reply
Yes, if you looked at the idea of god as an unprovable truth or falsity. However, as soon as you regard God as innately and rationally undecidable, Bertrand's paradox is sidestepped without any help from Godel.

>>11893

You don't need (and cannot expect) a rationally coherent argument to prove something that is by nature unprovable. People use methods other than reason to decide whether or not something is true, and that's where ineffable faith comes in to the picture. Judicious use of reason points away from and outside of itself, as Godel found.


help solving equation for chemistry by Cedric Dreckleludge - Thu, 04 Apr 2013 07:11:01 EST ID:2UcT5X7K No.11259 Ignore Report Reply Quick Reply
1365073861693.png -(89456 B, 674x382) Thumbnail displayed, click image for full size. 89456
I'm studying chemistry, but I have very little math background. Could someone please walk me through the steps to solving equations like the one in the image, or link me to somewhere that explains it? Thanks.
>>
Cedric Dreckleludge - Thu, 04 Apr 2013 07:53:14 EST ID:2UcT5X7K No.11260 Ignore Report Quick Reply
Basically, I don't understand if the first C and M are variables or if they are just indicating what the numbers that come before them are. Also, I don't know what to do with the second C and M or the D.
>>
Hedda Dronningfidge - Thu, 04 Apr 2013 11:10:18 EST ID:CnUI6Dgs No.11262 Ignore Report Quick Reply
mu = Q * r
Q as mentioned above is the charge of one of the poles, so Q = 1.6*10⁻¹⁹ C
(C stands for Coulomb and is the unity of charge.)
r is the distance between the two poles, so r = 100 pm = 100 * 10⁻¹² m = 10⁻¹⁰ m
(m stands for meter and is the unity of distance, p stands for pico and is a 10⁻¹² factor.)
So mu = 1.6 * 10⁻¹⁹ * 10⁻¹⁰ Cm = 1.6 * 10⁻²⁹ Cm

The next step is changing the unity from Cm to D.
Since 1 D = 3.33*10⁻³⁰ Cm, you get 1 Cm = 1/(3.336*10⁻³⁰) D.
Finally,
mu = (1.6*10⁻²⁹)*(1 Cm) = (1.6*10⁻²⁹)/(3.336*10⁻³⁰) D = 1.6/3.336 * 10 D ≃ 0.48 * 10 D = 4.8 D

I hope this is clear enough. I'll be around if you have any more questions.
>>
Lillian Pannerdock - Fri, 05 Apr 2013 07:38:54 EST ID:2UcT5X7K No.11266 Ignore Report Quick Reply
>>11262

Thank you! That helped a ton!

*feeds you a biscuit*
>>
Basil Chendernerk - Tue, 18 Jun 2013 01:57:30 EST ID:856TcHmP No.11900 Ignore Report Quick Reply
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DICKS EVERYWHERE


There is no negative number. by Martha Blivingwell - Fri, 31 May 2013 14:34:58 EST ID:sWOk+QGU No.11787 Ignore Report Reply Quick Reply
1370025298784.jpg -(52841 B, 250x250) Thumbnail displayed, click image for full size. 52841
"-10 is not a negative number. It is mathematically MINUS as in the operation, but that it exists shows that it is positive. There is only positive, into infinity and then lack of a number. This fits the definition which is so clear with every other subject of study. Speed: No negative speed exists, only none and speed into infinity. Heat: No negative heat exists, only none and then heat into infinity. Size: There is no negative size, only non-existence and then size into infinity. So it is with the universe. Matter: it is. It exists and then onward into infinity, things exist to intricacy infinitely as well. I can either go infinitely into 2. e.g. 2.1111111111111111 into infinity. I can also go infinitely in size. 21111111111111111111111 etc. So there are three laws: Outward, Inward, and Non-existence. There is no such thing as negativeness."
7 posts omitted. Click Reply to view.
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Mr Smells - Wed, 05 Jun 2013 23:06:27 EST ID:dhANKuZP No.11831 Ignore Report Quick Reply
>>11828

The breaking of space-time fabric like you would put your finger on your shirt. Your finger presses inward, subsequently "bending" the cloth fabric inward.
>>
Phineas Shittingdale - Thu, 06 Jun 2013 12:32:43 EST ID:g9W50kA4 No.11836 Ignore Report Quick Reply
>>11831
You know "inward motion" as you describe it is just "outward motion" from a different frame of reference? That was already handled by physics a long long time ago. Congratulations on discovering the "number line" they teach that in kindergarten here, to help visualize basic arithmetic and coming to the groundbreaking discovery that A-B= A+ (-B)
>>
Finger Game - Thu, 06 Jun 2013 23:03:38 EST ID:dhANKuZP No.11838 Ignore Report Quick Reply
>>11836
No need to be cheeky here. Yes I know the part about perspective, but I am saying let the fabric be fixed so that the viewer has only one reference.
>>
Edwin Dingermidge - Sun, 16 Jun 2013 21:46:33 EST ID:g7Lb6+Wn No.11896 Ignore Report Quick Reply
1371433593043.gif -(501751 B, 167x250) Thumbnail displayed, click image for full size. 501751
>>11838
I think hes being sarcastic because this thread is a shit show of people who dont actually know mathematics or sufficiently advanced physics to know they're wrong
>>
Mr Smells - Mon, 17 Jun 2013 00:13:46 EST ID:dhANKuZP No.11897 Ignore Report Quick Reply
>>11896
A few people here are qualified. I would say most arent; that includes me


Antarctic Mystery by Fanny Dovingshit - Sat, 01 Jun 2013 19:35:50 EST ID:72FsLw8N No.11806 Ignore Report Reply Quick Reply
1370129750428.jpg -(88676 B, 1253x589) Thumbnail displayed, click image for full size. 88676
Hello everybody, we've got something of a mystery over at /b/. The quick and dirty of it is that google maps has some Antarctic land that appears to be blanked out.

http://boards.420chan.org/b/res/3168728.php

I thought maybe these blanked out areas are just artifacts left from the transition of a sphere (the earth) into a 2 dimensional rectangle (the map), but I haven't into maths or geography in a while so I'll go ask I'd ask you.

On an unrelated note, how best should I go about learning mathematics? I just started doing khan academy exercises after about a year or so of taking it easy, so to speak (I regret this very much). I also have quite a few math (and technology) ebooks. If I cut down on smoking cannabis will that help? What about smoking more? Eventually I want to understand lambda calculus and code lisp, pretend I'm a knight and shit.

But enough of my rambling, what do you think?
>>
Alice Nicklefoot - Sun, 02 Jun 2013 16:47:35 EST ID:MTIV7/tU No.11810 Ignore Report Quick Reply
>>11806
I guess it could be artifacts like you suspect, but I don't know how Google Earth coded the surface, so I have no way of verifying this.

I can't really help you on starting math again, since I haven't taken a break yet. But concerning your cannabis question, I gotta say I know some guys who do math only when they are high, and they have great results. I tried once and I did well too, but maybe it was only because I was doing some pretty abstract stuff, had there been any serious calculation to do and I doubt it would have gone this well. I guess I'd recommend you to maybe take a little cannabis break for beginning, then try working high and decide from there on.

Good luck.
>>
John Gorrysidge - Sun, 16 Jun 2013 17:50:48 EST ID:7KaSSwki No.11892 Ignore Report Quick Reply
1371419448365.jpg -(47329 B, 598x530) Thumbnail displayed, click image for full size. 47329
This post is quite the coincidence. I am the OP of the antarctic artifact thread, and I too am attempting to learn math after a long period of none for a university program I'm switching into. Khan Academy is working very well for me so far and I would highly recommend it. The skill levels is encompasses are very broad, so if anything has you stumped you can easily look back at previous concepts to see why it isn't working. Best of luck to you!


What is your favorite calculator and why? by Shit Nickleville - Fri, 29 Mar 2013 01:18:30 EST ID:rN65bcH4 No.11224 Ignore Report Reply Quick Reply
1364534310501.jpg -(32052 B, 640x427) Thumbnail displayed, click image for full size. 32052
Math, what is your favorite calculator and why? what do you use it for, what features make it stand apart from others? what don't you like about it?

my preference is a casio classpad 330. several years back in a calc2 class we were given them by a casio rep to test and keep in exchange for our feedback.

split screening in graphs/tables etc is very nice, also has auto window sizing methods and shit. im a very visual person, it makes seeing things quick and easy.

my absolute favorite part is the 2d representation. you can literally build things as they look on paper, quick and easy. it makes it super easy to check your work or evaluate complicated things without having to fight with a billion parentheses.

easily evaluates integrals both definite and indefinite (not that im at all dependent but it could honestly be defined as a cheating machine), including the nasty tables that i don't care to read though. so much easier to just type it it and get an answer.

cons: bit of a learning curve to figure functionality but its a very powerful device for everything ive seen. i don't know how it compares for much more complex mathematics

highest level of math: integral calculus, some multivariable calc.

i also have a ti-86 plus and a ti-84 plus, neither of which i use.
9 posts and 4 images omitted. Click Reply to view.
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Graham Gunningson - Tue, 02 Apr 2013 20:39:53 EST ID:rzaTGV2V No.11254 Ignore Report Quick Reply
I have a ti-89 emulator for my smart phone for anything that needs to be done on the go which is complicated... because I'm out of school that basically never happens.

Tbh, if it's not something super complicated that I need matlab/r/eviews for, I just use wolfram alpha these days. I'm pretty much always near a computer anyhow (and they have a mobile app).

tl;dr there's not really a good reason to use a calculator these days other than maybe the fact that some of them are solar powered.
>>
Eliza Goodfuck - Tue, 11 Jun 2013 10:34:25 EST ID:iVTUM30L No.11865 Ignore Report Quick Reply
>>11254
seconded, in the modern age wolfram is the way to go
>>
Sidney Fomblestug - Fri, 14 Jun 2013 07:10:56 EST ID:d8qpzp+a No.11887 Ignore Report Quick Reply
1371208256172.jpg -(121941 B, 800x1154) Thumbnail displayed, click image for full size. 121941
I liked my TI-83+ for a long time, had it for about 7 years. Did most stuff I wanted it to and I never needed a calculator much during my degree anyways.

Lately I've studying for actuary exams and they only allow a select few calculators so I've been using a TI BA-2 Plus pro. Basically just a glorified scientific calculator.
>>
Cyril Bardfield - Sun, 16 Jun 2013 00:04:12 EST ID:g7Lb6+Wn No.11890 Ignore Report Quick Reply
>>11230
fucking truth dude
I actually bought another casio fx-115es when mine broke, because its really fucking easy to use and i love it for geometry/algebra
>>
Eugene Dartwill - Sun, 16 Jun 2013 12:22:03 EST ID:F9AJX/Os No.11891 Ignore Report Quick Reply
i've got a TI-89, which I use for all heavy-duty calculations when I'm on the go and don't have any other computer available.

Besides that, I've got this rockin' scientific calculator that I've had for like 10 years now. Still works perfectly, and if I need something fast I use this instead of the more clunky 89.


mathematical induction / proofs by Ebenezer Bardwell - Sun, 09 Jun 2013 04:39:57 EST ID:cgM57Kwa No.11846 Ignore Report Reply Quick Reply
1370767197899.jpg -(581318 B, 960x1280) Thumbnail displayed, click image for full size. 581318
Ok so I'm terrible at math but I try, trust me I try. I don't understand why this doesn't work as I followed all the steps the book gives me to do math induction, but I still get it wrong, if you see the picture, the first term can't possibly be equal to the second, it would give me a huge number and the second one a low one. I beg for your help, just point me in the right direction or tell me what I did wrong.
1 posts omitted. Click Reply to view.
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Lydia Bicklespear - Sun, 09 Jun 2013 06:30:30 EST ID:ez5ALJXV No.11848 Ignore Report Quick Reply
>>11847
er, actually sorry, not the sum, the product
>>
Ebenezer Bardwell - Sun, 09 Jun 2013 13:35:34 EST ID:cgM57Kwa No.11850 Ignore Report Quick Reply
>>11847

Thanks for your answer, but I still don't get it. Isn't what you just said what I did?

I proved that it was true for n = 2, I assumed it was true for arbitrary k, then for k +1. And the operation should be first second term (assuming k) * first second term (assuming k +1) is true for second second term.
>>
Lydia Bicklespear - Sun, 09 Jun 2013 17:54:47 EST ID:ez5ALJXV No.11853 Ignore Report Quick Reply
>>11850
No, you do not assume that it is true for both k and k+1 , you have to SHOW that if it is true for some k, then it necessarily is true for k+1. Start with your assumption that it is true for k, multiply both sides by the term that would make the left half equal to the sum for k+1, (which would just be (1- (1/(k+1))) right?). Then use arithmetic to show that the right half equals ((k+1)+1)/(2(k+1)). That it is how you use induction.
>>
Martha Hisslemurk - Fri, 14 Jun 2013 05:00:17 EST ID:UGqI7eRS No.11886 Ignore Report Quick Reply
>>11846
Logical errors aside, the last line should have a multiplication sign between the two major expressions:
[(k+1)/(2k)] * [1-1/(k+1)^2].

Then you will get
[(k+1)/(2k)] * [1-1/(k+1)^2] = (k+1)/(2k) - [(k+1)/(2k)] * [1/(k+1)^2] by distribution
= (k+1)/(2k) - (k+1)/[(2k)*(k+1)^2] multiplication of fractions
= (k+1)/(2k) - 1/[(2k)*(k+1)] eliminating like terms in second expression
= (k+1)^2/[(2k)*(k+1)] - 1/[(2k)*(k+1)] finding the common denominator
= [(k+1)^2 - 1]/[(2k)*(k+1)] adding fractions
= (k^2 + 2k + 1 - 1)/[(2k)*(k+1)] FOIL on (k+1)^2
= (k^2 + 2k)/[(2k)*(k+1)] definition of additive inverse
= [k*(k+2)]/[(2k)*(k+1)] distributive property ("pulling out" the common term)
= (k+2)/[2*(k+1)] eliminating the common multiple k from numerator and denominator
= (k+2)/(2k + 2) distributing the 2
Comment too long. Click here to view the full text.
>>
Priscilla Bramblekack - Fri, 14 Jun 2013 23:36:14 EST ID:A3ou2w4x No.11888 Ignore Report Quick Reply
It's critical to prove from one side of the equation as well.
In particular, look at step 1.
You should show that 1-1/(2^2) = 3/4
and then show that (2+1)/(2*2) = 3/4

They shouldn't be shown at the same time, on opposite side of an equation. Writing it like that assumes that they are already equal and you should get used to writing it properly, it'll come up repeatedly.


Calculating Combinations by Augustus Gennerson - Sun, 28 Apr 2013 03:08:31 EST ID:GaVlYA/B No.11458 Ignore Report Reply Quick Reply
1367132911098.jpg -(68401 B, 834x555) Thumbnail displayed, click image for full size. 68401
Hi /math/, I haven't done any in a long time, so I'm hoping someone will pity me and offer assistance. I am trying to figure out how many possible combinations there are for a team of 12 players, in which the games only have 3 play per match.

I have the dumb, so all I know is 12/4=3, and 12/3=4, and 3*4=12, and 4*3=12 and blah blah multiples, lowest common denominator blah blah.

How does I calculate this?
>>
Phineas Tootfield - Sun, 28 Apr 2013 13:03:51 EST ID:bpNm376E No.11461 Ignore Report Quick Reply
>>11458
You have 12 players and you need to choose 3 of them so 12!/(3!(12-3)!)

https://en.wikipedia.org/wiki/Combination
>>
Emma Denderwodge - Sun, 28 Apr 2013 17:13:41 EST ID:MTIV7/tU No.11463 Ignore Report Quick Reply
>>11461
And that's 220, if you don't know binomials.
>>
Doris Nugglefit - Wed, 08 May 2013 11:18:37 EST ID:F9AJX/Os No.11548 Ignore Report Quick Reply
>>11463
and thats 11011100 in binary, if you don't know the decimal system
>>
Shitting Fuckingwell - Wed, 08 May 2013 12:09:13 EST ID:X70kgTC4 No.11549 Ignore Report Quick Reply
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>>11548

1101110
>>
Shitting Fuckingwell - Wed, 08 May 2013 12:16:00 EST ID:X70kgTC4 No.11550 Ignore Report Quick Reply
>>11549
Disregard this. I don't even.


Kinematics by Cyril Bunderdale - Fri, 07 Jun 2013 23:55:34 EST ID:dBqEfWzs No.11841 Ignore Report Reply Quick Reply
1370663734916.jpg -(59871 B, 700x460) Thumbnail displayed, click image for full size. 59871
Acceleration is the rate of change of velocity, which is in turn the rate of change of displacement, so displacement can be calculated by integrating acceleration twice. Acceleration due to gravity varies as the inverse square of distance, which is affected by the displacement. So is distance then defined in terms of itself?

Like, say for the sake of argument you have a particle 1 meter away from a fixed attractor with mass of 1 kilogram. The particle has initial velocity 0. How do you find its position after 1 second?

Mathematica gives me a max recursion depth error.
>>
Ian Guddlestock - Sat, 08 Jun 2013 04:47:17 EST ID:3r+MBiFX No.11842 Ignore Report Quick Reply
Why would acceleration due to gravity vary?
>>
Lydia Bicklespear - Sun, 09 Jun 2013 04:18:08 EST ID:ez5ALJXV No.11845 Ignore Report Quick Reply
>>11842
well, if you have a particle falling from a significant distance away from a gravitational attractor, because gravity is an inverse square law, the field is not constant. you can only ignore the variance of the gravitational field at different radius' for changes in height much much less than the radius of the earth.

As per the OP, I would say the best way to solve this problem would be to solve for the velocity as a position of function using energy, and then integrate.
>>
Mr Smells - Mon, 10 Jun 2013 19:08:48 EST ID:dhANKuZP No.11861 Ignore Report Quick Reply
>>11841
acceleration is derivative of velocity, and displacement is integral of velocity. So the change in displacement is the velocity. Right?
>>
Lydia Blackson - Thu, 13 Jun 2013 18:15:19 EST ID:neuqxMMW No.11883 Ignore Report Quick Reply
>>11861
In this case acceleration is a function of position, however


Mathematics in relation to computer engineering by Cyril Buzzbanks - Tue, 11 Jun 2013 12:01:56 EST ID:Z1HtT+U2 No.11867 Ignore Report Reply Quick Reply
1370966516812.jpg -(131917 B, 1920x1200) Thumbnail displayed, click image for full size. 131917
I'm currently studying computer engineering, and have taken it upon myself to get ahead as much as possible this summer. However, in doing that I've noticed that my main focus has been towards ensuring I understand the things in Java that I didn't last semester.
I'd like to also start teaching myself some mathematics, however I'm not sure where to begin. We did an introduction to differential calculus course, but aside from that nothing. My main concern is that I want it to either be something that is very helpful to computer engineers, or is just very useful to know in general. Eg: Ever since watching a beautiful mind, "game theory" always interests me whenever I hear it mentioned but I don't really know if that is worth my time to learn.

If anyone could maybe leave a list of a few topics I should study, would be greatly appreciated.
Thank you.
>>
Simon Sommerchene - Tue, 11 Jun 2013 16:57:08 EST ID:sPd/0oB/ No.11869 Ignore Report Quick Reply
What do you like? What are your hobbies?

If you like game theory, then why don't you simply learn about game theory?
I suggest you read about the minimax algorithm, with alpha/beta pruning and shit like that. It's between game theory and computer science so you might like it.
You could make a cool game and a cool AI to go with it. Like an online othello or something like that. The game itself is more /prog/, while the AI is more /math/.

If you prefer algebra and calculus then you could make a 3D game with pixel/vertex shaders. 3D engine are full of matrices and quaternion everywhere. A shader is basically a program to manipulate functions. Even a simple animation is math, it's just a function of time to your screen.
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Betsy Shakelock - Tue, 11 Jun 2013 22:58:54 EST ID:Z1HtT+U2 No.11873 Ignore Report Quick Reply
>>11869
I don't think my programming skills are quite good enough yet to make games, the closest I could get is to use a previous OpenGL program I made in class that just displayed moving particles that formed a pixelated pac-man, and get it to use input to determine movement of those particles and such. Not much math involved there, unless I were to get into gravity and stuff like that.
I think I might just pick at my textbook.
>>
Alice Wugglehick - Thu, 13 Jun 2013 15:22:38 EST ID:6stlnvc+ No.11882 Ignore Report Quick Reply
1371151358881.jpg -(215063 B, 1024x768) Thumbnail displayed, click image for full size. 215063
For useful/interesting mathematics to learn,
Linear Algebra is practically mandatory to do anything interesting or large scale in CompE so go as deep as you can down that rabbit hole.
Abstract Algebra and Group Theory appear everywhere including CompE and it's one of the most interesting areas of mathematics so definitely take a look if you have time.
(Non-Euclidean) Geometry especially projective geometry appears a lot in Comp Vision, Robotics, Comp Graphics so it would be very beneficial to read through college level geometry book like Brannan before you run into those topics and quickly get lost.

Complex Analysis, Fourier Analysis, PDEs, and Functional Analysis are also important but trying to learn them by yourself might be a little too difficult at your level...

>Computer Engineering
>Java

Why the fuck are you wasting your life learning Java? Learn C++/Python/Matlab/ARM/Verilog, something useful for your profession...


sick extreme value problem by Jenny Crunnerstone - Wed, 12 Jun 2013 17:57:47 EST ID:pgEOJeMx No.11877 Ignore Report Reply Quick Reply
1371074267097.png -(27798 B, 774x694) Thumbnail displayed, click image for full size. 27798
the problem is:
"Find the the point P=(X',Y',Z') on the ellipsoid
(1/25)*(x^2) + (1/16)*(y^2) + (z^2) = 1, with X', Y' and Z' > 0,
such that the volume enclosed by the tangent plane on the ellipsoid in P and the coordinate axes is minimal."

The 1/16 and 1/25 may not be the values of the original problem, this is the best I can remember. Regardless, a solution has to exist for any positive coefficient of x and y, because Bolzano and Weierstass say so.

I'm using maple over vpn on my school's server, and this is the first time a solve command took more than a minute.
I'll post my progress tomorrow, I've spent hours on this problem today, it's probably because I didn't get enough sleep that I can't solve this shit.
In the meantime, any insights or tips are most welcome. This is not my homework or anything, in fact, let's make this a thread for challenging math-problems in general.


adding and subtracting vectors by Hamilton Farrytare - Tue, 11 Jun 2013 19:04:08 EST ID:NwJ997Qt No.11872 Ignore Report Reply Quick Reply
1370991848512.jpg -(1819484 B, 2560x1920) Thumbnail displayed, click image for full size. 1819484
Okay I have No idea How to subtract vectors. For adding, I know that you break it down intp its X's and Y's Then add the two components and Pythagorean theorem. But How do you subtract?
>Pic related, I'M suck on number 13.
Would you put Vector B as 26.5 at 236 degrees instead of 26.5 at 56.0 degrees? Please help.
>>
Emma Drammernit - Wed, 12 Jun 2013 05:56:25 EST ID:g9W50kA4 No.11875 Ignore Report Quick Reply
subtracting a vector is the same as adding a vector of the same magnitude but opposite direction. If the vector that was to be subtracted was at magnitude 3 at 90 degrees, it would be the same as adding a vector of magnitude 3 at 270 degreees.
>>
Name - Thu, 13 Jun 2013 02:25:23 EST ID:tQF0J/8J No.11879 Ignore Report Quick Reply
1371104723082.png -(184626 B, 700x856) Thumbnail displayed, click image for full size. 184626
Strictly algebraically: You can just subtract the components of B from the components of A.

Geometrically: A - B means, assuming you understand how to add vectors, that you add A and -B. If it makes it easier for you to think about, -B is just B in the opposite direction, so you can draw the negatives of each vector and simply treat them all like addition. I hope we helped. I know I said the same as the other guy, but different wording helps for different people. nb since redundancy.


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