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https://sites.google.com/site/scienceandmathguide/
>>
If you want advice with college/university, go to /adv/.

>>>/adv/

Reminder: /sci/ is for discussing topics pertaining to science and mathematics, not for helping you with your homework. See the rules page for details.

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Hey /sci/, I'm really bad at calculus. Can you help me understand differential equations?
So I have a differential equation:
4y'' - 4y' + y = x*e^x + 2x - 16
And I can solve the homogeneous case for when the left hand side is equal to 0, which is a half, which tells me I have repeated solutions such that y takes the form y = Ae^(x/2) + Bxe^(x/2) where A and B are some real constants. But I don't know how that helps me solve the inhomogeneous case and hence solve an associated initial value problem. Where do I go from here?
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>>7264413
so I did it except the last step and I got

y(x) = xe^x - 4e^x + Qe^(x/2) + [24a_3 - 8a_2 + a_1)x + (8a_2 - 4a_1 + a_0)

where Qe^(x/2) is your general solution you'd get from the rest of the serious after pulling out the a_n to satisfy the 2x-16.
the a_n's might be arbitrary, but i didnt' feel like solving them
>>
>>7264411
do they even offer "computer science" as a major?
i thought all they had was informatics (the sample coursework i viewed made this look like information technology) and software systems (software eng.).
>>
>>7264707
Computing and Software Systems is a more CS-focussed major, even though it sounds software eng-y. That's what I'm doing. What about you anon?
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>>7264169
METHOD OF UNDETERMINED COEFFICIENTS
learn it
>>
>>7264783
>4y'' - 4y' + y = x*e^x + 2x - 16

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Hey /sci/

Inspired by Scott Young's MIT Challenge. I plan to complete MIT's Theoretical Mathematics curriculum (12 subjects) in one year using MIT Open courseware. This means that I will have to do 1 subject a month. Does /sci/ have any advice or comments about this? I have attached the subjects I plan to do. It excludes only one subject; MIT's seminar subject. I replaced it with Street Fighting Mathematics.
7 replies omitted. Click here to view.
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>>7264766
All the upper level electives:

PDEs, Complex Analysis, Algebraic Topology, Differential Geometry, Mathematical Logic, Analytic Number Theory, etc

>>7264773

Just realistic
>>
>>7264775
Nope you are wrong I refer you to their page: https://math.mit.edu/academics/undergrad/major/course18/theoretical.php
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>>7264775
Algebraic Topology is a graduate level course not undergraduate.
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>>7264778
No, it's firmly undergrad.
>>
>>7264776
I'm not him but this is intriguing, so you really only need these few courses? Then I can tell you that for certain, Analysis will be extremely tough, here let me recommend you a proof book you should go through before you progress to analysis. Single, multi, DEs are really easy, Analysis is something new though, that is when you learn how to prove.

http://www.people.vcu.edu/~rhammack/BookOfProof/BookOfProof.pdf

I used this personally, if you don't like it there should be other recommendations on the wiki. Do this at the same time with Calculus.

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Are intuitionist mathematics complete? Complete in the sense that every theorem of intuitionistic mathematics can be derived from a given set of axioms.

TAs or faculty members (>Implying) of /sci/,

How do you handle students crying in front of you? It's always the most arrogant girls too who's egos start getting crushed at the first difficult upper level courses. Somehow I always end up looking like an asshole for not giving them marks they don't deserve.

Also my prof. is usually apathetic if they break down during tests and run out crying. Is he delegating the task of calming them to me or am I just supposed to ignore them?

Also general STEM TA/teaching thread, share your stories and frustrations.
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>>7264752
What do you mean by "things" and "success"?
>>
>>7264755

that depends on the view of people.

if you are extraordinary at sucking dick, obviously people will come to you to get their dicks sucked.
>>
Is Chemistry that hard then? I don't have to do any classes other than my major, but I thought it wouldn't be more difficult than Maths or Engineering
>>
>>7264764
I don't have time to explain to you why the real world doesn't work like a medieval village.

Just get scholarships or a corporate bursary and get the papers, don't be stupid.
>>
>>7264772
but a medieval village is part of the real world.

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So light colour for the eyes is always been known as being weaker. But what are the advantages of them?
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>>7262669
>>7262672
which countries are you living in?
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>>7260309
Lightly pigmented eyes see better in polarized light conditions, such as glare off of ice or the surface of the water you might be fishing in.
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>>7264183
Me too, it's always the eyes; as for the latter: Italy.
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>>7264758
same here
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>>7260339
I think the main reason why non-brown eyes are seen as attractive is novelty; similar to why we find average foreigners attractive. Also the reason why some people connect terabytes of porn, it's all about finding novelty in a mate, maximizing chances of an ace genetic mix.

Though we are varied so not everyone seeks novelty, some are naturally more racist.

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What is the equation that have the most aplications in real life?
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>>7260993
Jet fuel + steel beams =/= molten steel
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>>7263617
9/11 ign
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>>7261230
This
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>>7261074
>looking to expand into the realm of quadruple integrals

I dont know man... the quad-integral market doesn't seem to be so prosperous at the moment
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>>7260993
calories in = calories out + fat stored
volume gas used * mileage = distance driven

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So if the Out of Africa theory is incorrect and the Multiregional theory true, how much impact did the african migrations have on the population?
>>
Increase of crime and theft, thus promoting societies with a more restrictive controll of the nobility/chieftains/shamans over the rest of the population and ultimativelly leading to the first civilizations. Thanks Tyrone.

What is it? Ayyliens? Ice?

Larger gif
>https://www.nasa.gov/sites/default/files/thumbnails/image/pia19547-1041b.gif
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>>7262575

It's a 3D projection constructed from 2D data of a 3D object from different perspectives; the flyby animation was assembled. Assembled != faked.
>>
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From the Dawn mission update page:
May 15, 2015 - Dawn Spiraling Lower

Dawn is using its ion engine to maneuver to its second mapping orbit, which will be 2,700 miles (4,400 kilometers) high. It will reach that altitude in early June.

During the course of the day today, Dawn’s altitude will decrease from 5,500 miles (8,900 kilometers) to 4,800 miles (7,700 kilometers).

Tomorrow the spacecraft will pause ion-thrusting to take pictures of Ceres for navigation.

http://dawn.jpl.nasa.gov/mission/status.html
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>>7255663
>God I just want them to find something before I die.
We have found elusive evidence of Dyson Spheres and engineered galaxies.
There is also the mysterious Dark Flow.
Plenty of evidence of artificial engineering of the universe.
But on a scale of billions of years ahead of us which we can't distinguish clearly from natural processes, because they are so gigantic.
>>
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>>7256609
One of the most fascinating objects in Solar System is Triton.
It has atmosphere, cryovolcanos, probably subsurface ocean.
We have only seen it once.
>>
>>7264754
Maybe we'll see Herschel and La Verrier-Galle/Lassell probes in our lifetime to follow up on Galileo and Cassini-Huygens.

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A read-only Turing machine is equivalent to a DFA, is this also the case for a Turing machine that can read and write, but only on the part of the tape where the input is/was?
I.e. a bounded Turing machine, but where the markers are immidiately before and after the input?
>>
>>7264687
>is this also the case for a Turing machine that can read and write, but only on the part of the tape where the input is/was

No, it can recognize palindromes with ease.
>>
>>7264741
You're right, thanks

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Let's ask some stupid questions that don't deserve their own thread.
I'll start.
I have an undirected graph matrix G represents a forest.
Now I need to decompose G into k smaller graph matrices, each represents a tree.
What is the fastest way to do this in MATLAB/OCTAVE?
I wrote a recursive function on my own but I think there must be a better solution that I missed in my Discrete math class. Or maybe not.
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>>7264335
post your code
dont copy paste, post screen shot
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>>7264180
is it precum or an actual load? precum is normal.
>>
>>7264459
get x1 from one row, put that into another row and get x2 from that row, and so on until you only have x4 = whatever, then take the row with x3 and x4 and replace x4, and so on
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>>7263280
pls respond
>>
>>7263280
>I got a B+ in Calc 2
>>7264705
gg

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Yo /sci/, I haven't been on here since this board was first up in like, '10 or '11 or whatever so I don't know shit about science
I found this doujin though and it seems to spout a lot of scientific stuff and was wondering if you guys would verify or explain how accurate it is.
This is the exhentai link but I'll dump it anyway in case you lot can't figure out the science of sadpanda.
Oh and no nudity, just lewdness
http://exhentai.org/g/705632/02a56dd483/
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>>
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>>7264248
Don't stop!

>>7264241
It's legit. Doing work with heat entails heat transfer to a lower temperature state.

Not sure how the ice would interact with something colder than it.
>>
>>7264566
The shit about time manipulation causes this to be so retarded.

Even if the energy from the air surrounding the time frozen ice would attempt to travel to it, it won't reach it. Because it's stuck in a state of zero change. So where does this energy go? I'd say that the force causing the energy to move to the ice wouldn't magically stop, but that the energy would be stopped at the border of where the ice's physical state in time is being suspended, essentially creating what used to be considered a firewall around event horizons.

I'd also add that relative to the surrounding air, it wouldn't even need to be ice which is being suspendrf in time. What does an object whose molecules have stopped all motion and thermal energy values are 0 sound like? Sounds like absolute zero to me. So really ANY object suspended in time would simulate or outright achieve absolute zero and have the exact same effect. That is, if the suspended object is even still capable of emitting a force of attraction.
>>
>/sci/ once again proves that it is comprised of people who barely graduated from high school.

>>7264617
This anon at least gets credit for being able to read.
>>
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>>7264241
>2a is right
>2b is bullshit as frozen time can't interact with shit
>4 is bullshit, the heat would see the cube as invisible
>5 only if 4 was right and you have 2 cubes at different temperatures

You need an ESPer like this for that.

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Discuss.
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>>7264536
Can't put a black hole ON a scale.

Checkmate atheists.

Atheists: 0
Pagans: 1
>>
>>7264539
But black holes are made of matter with finite mass but infinite density. Couldn't you just measure the mass before it became a black hole?
>>
i say 1.5
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>>7264050
>By your logic if 500g of flies were flying above a set of scales the scales would pick them up.

Are you implying they stay aloft without causing a downwards pressure on the air with their wings?

Are you implying they DO cause a downwards pressure on the air but that the air, being pressed upon, collapses instead of pressing on the scale?

What is your endgame here?
>>
>>7264037
The flies aren't inanimate objects suspended in air. They are moving.

Suppose you are in a closed box on a scale. Now you jump up and down. The scale will not at all times display the same weight, but fluctuate. So you will have a closed system that at times weighs less than its enclosed mass.
But since 500 grams of flies are a lot of flies, that effect will probably be negligible.

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I need to "re-learn"(study) highschool math in a week, can I do it? I have time to study everyday.
Is there some book(or what books) that covers all the topics?
I tried some basic equations yesterday and after some minutes, everything was coming back.
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>>7262170
>>7263278
http://www.gallup.unm.edu/~smarandache/MyHighSchoolMathNotebook1.pdf
this seemed to be the best one I found, although I assume you also googled "high school math notes pdf"
>>
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>>7263316
op here, I'm back.
thx for the link dude, tbh I never knew that something like that existed...
>mfw
>>
for what exactly? the only math that would require "studying" would be trig, and yes you can relearn trig in a day. I did going into calc 1 my freshman year
>>
>>7264064
>for what exactly
what do you mean?
>>
>>7264110
I think he'd like to know why you'd want to relearn ALL of highschool math, and not just specific parts of it.

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/sci/ humour thread
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>>7264606
Astronomical means "Very large", and units are another name for a house
>>
>>7264550

The given algorithms will get you to a solution, but it won't always be the fastest solution. The tricky part is trying to find a way to get from any unsolved state to a solved one in the shortest number of moves.
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>>7264717
I know an algorithm that will find the shortest algorithm for any state
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>>7263129
I approve this joke
>>
>>7263129
My dad is a chemist and growing up this was one of the equations he'd keep spewing at me and telling me how hard it was to solve (He actually said it was H \psi = E \psi ). Growing up I could not figure out why he didn't just cancel out the \psi and get H=E


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