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x + 3^x < 4
Is there analytical solutions?
Help a retard.
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>homework
Go to /wsr newfag
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wat is a log
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>>8491716
>x + 3^x < 4
lol naplet.
x+3^x = (1 + 3^)x
-> x < (1+3^)^-1 * 4 =(1 + 1/3) * 4 = 5 + 1/3
on a serious note:
x + 3^x = 4 for x = 1. the function is strictly monoton therefore for any x < 1 it is < 4
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For an algebraic stack [math] \mathfrak{X} \to {S_{Et}} [/math] , what is intuition behind requiring the diagonal morphism [math]\mathfrak{X} \to \mathfrak{X}{ \times _S}\mathfrak{X}[/math] to be representable?
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Ok so I have been playing with the definition and this seems to imply that schemes over stacks with representable diagonal can glue to give more schemes.
Am I on the right track? Someone on /sci/ must know this.
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/sci/ is useless
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>>8492197
most /sci/-goers aren't math grad students
try the math stack exchange
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So a while back they discovered that when old mice are transfused with blood from young mice it made the older mice younger. This led to the belief that young blood has something in it that makes you young again.
http://www.nature.com/articles/ncomms13363
This newest study says that's incorrect. It's old blood that has something in it that makes you age faster. There was never anything in young blood that makes mice/people young. Replacing old blood with new blood just removes the chemicals in old blood that make you age.
My question is should blood letting and leaches be reexamined for medicinal value? If old blood has shit in it that makes you age, and can't be filtered out naturally, then blood letting and leaches should remove it. This was the working theory back in the day before it was abandoned. Why did they abandon it? What specific evidence or proof did they have to doubt blood letting other than too much can kill you?
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>>8490309
>bloodletting
>leeches
Couldn't you just make blood donation mandatory for everyone without a blood-transmitted disease?
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>>8490327
Obviously blood donation is the modern day version of blood letting and leaches. Having a nurse, that pays you money, to monitor your vitals eliminates that dangerous side effect of taking blood letting too far.
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"Old blood" isn't that old, all of the cells have a limited life span and are replaced continually, and fluids are added/removed constantly. Taking blood and then replacing it with blood made internally by an "Old" person isn't going to be that different. A complete exchange transfusion of blood from younger donors may be different (although repeat transfusion is a bad idea for various reasons, including risk of tti that goes up with each donor exposure, development of allo antibodies, iron buildup and required chelation, risk of transfusion reaction or trali, or other transfusion associated organ injury, etc.).
What are these "things in old blood" that have an effect?
Anonymous
How do I come up with a topic for my Honors Undergrad Thesis in Stats? 2016-11-22 16:03:50 Post No.8490071
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How do I come up with a topic for my Honors Undergrad Thesis in Stats? 2016-11-22 16:03:50 Post No.8490071
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How do I come up with a topic for my Honors Undergrad Thesis in Stats?
Anonymous
2016-11-22 16:03:50
Post No. 8490071
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21 Posts / 5 Images
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Flip a coin
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>>8490071
Just drop out if you can't do it and become a codemonkey if you learned some CS
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>>8490071
>"A Differential Analysis of The Quantitative Function of Obfuscated Semitic Influence Upon The Mainstream Media".
Okay, OP?
Anonymous
Physics has entered the field of memetics 2016-11-22 15:58:12 Post No.8490065
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Physics has entered the field of memetics 2016-11-22 15:58:12 Post No.8490065
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Physics has entered the field of memetics
Anonymous
2016-11-22 15:58:12
Post No. 8490065
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>EM drive
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I miss troll science
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What's so surprising about a guy from the 17th century getting physics (completely) wrong?
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>>8490065
Nah the paper is getting DESTROYED and will likely be retracted at some point. AIAA isn't even a very good journal.
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Lets talk quantum mechanics.
I just watched https://www.youtube.com/watch?v=t5KIwIb-EWM and the "particles act as waves unless observed" just completely fucked my brain up.
But it doesn't answer some of the questions I have.
What level of observation is needed until it collapses from a wave into going through a particular slit?
They went over a recorder making a beep whenever one was detected going through the top slit, but did they ever take it steps further? They unplugged the recorder, and it went back to being a wave.
What would happen if they used the device to record it but never looked at the results?
What would happen if they used the device, recorded it, but then did a second run where they only recorded 1 particle and, since it only has a 50% chance of going through the recorded slit, use that to determine if you'll look at the recorded data or not. Basically use it's randomness against it to force it into giving an answer.
It would be unnerving if you did my proposed experiment and could tell what the result of the secondary recording would be based on the pattern. But then you get the mindfuck of deciding to not look at the results from the initial experiment anyways, would that alter the initial experiment even if you only decided to not look at the results regardless of the secondary experiment only after the results of the second experiment.
Another thing is what counts as an observer? Does it have to be human? What if the recorder only beeps in a sound only dogs can hear, and you put a dog in the room and no human observes the recorders results? Has anyone tried that?
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>>8489421
This post is definitely a joke right? You're being ironic.
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>>8489425
Basically my question is "what counts as an observer". Is it just the device recording the results or the human looking at the results?
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>>8489428
It's anything that interacts with the situation in such a way that the relevant information can be recovered. You can make the measurement, not look at the result and it will still collapse.
Anonymous
Help me with the cardinality of this set anons 2016-11-23 15:10:57 Post No.8491900
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Help me with the cardinality of this set anons 2016-11-23 15:10:57 Post No.8491900
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Help me with the cardinality of this set anons
Anonymous
2016-11-23 15:10:57
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>>8491900
There are 2^k ways to pick at least one element in intersection. The rest is trivial
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>>8491900
[math] 2^(m-k) [/math]
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>>8492017
[math] 2^{m-k} [/math]
My LaTeX is so bad
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Is this the official bacteria of 4chan?
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No, that would be the users.
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>>8491875
why is that so perfectly squared ? was it god?
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>>8492126
Probably CDIs
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>>8491496
OORRR WAS HE DANCEEERRRRR
edit: thanks for the gold, kind reddittor :)
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>>8491496
Excellent facial structure and great mastication muscles.
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>>8491505
Kek
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Explain to me how eels could have discovered electricity millions of years before humans did. Surely this proves how fucking ridiculous the concept of 'evolution' is
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>implying eels aren't ayys
we've got satellites, we've got radio tags, how could we possibly be having such problems finding out how they breed except that they are doing it in another dimension?
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If you wrap an electric eel around an iron bar you have an electro magnet.
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How come electric eels don`t get electrocuted in water?
What voltage do they carry?
Are they AC or DC?
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I just measured the circumference of my head and I technically have macrocephaly
What do I do with this information?
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Begin to correlate autism with macrocephaly
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>>8491309
Throughout my undergrad I had this weird recurring fantasy of writing a paper on head circumference and field, after I noticed that all my math profs had huge heads and my electives profs had smaller heads. I still wonder sometimes if an ethics committee would approve it. The correlation is so clear to students, I'm sure it would be statistically significant enough to publish
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>>8491317
a correlative data without theoretical explanation behind it is useless
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I'm retarted, so I need help with this: how did the author go from -12x+9y=7 to 9x+-12y=6?
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You're probably missing some information in the book. What subject is this?
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>>8491246
he didn't
those are different equations with different solutions
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>>8491246
-12x+9y=7 to 9x+-12y=6
divide everything by 9
y=7/9+4/3x
times by -12
9x+-12y=6
there
Does anyone know if the diff equation from pic related is solveable? Wolfram alpha won't give any results
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ha ha ha xd
no its non linear and looks cancerous as fuck. maybe try numerical methods?
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I just plugged it into my ti89, it doesn't directly solve it, but it does reduce it to the form int(bunch of y shit dy)=x+C, if you care to see it. potato quality image
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part 2, also used pi as the constant, and the @15 or @14 or whatever is the calculator displaying the constant of integration
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What do you guys think about philosophy of science when it's written by people who are actually scientifically literate?
Example: http://ndpr.nd.edu/news/24377-every-thing-must-go-metaphysics-naturalized/
Also see: Hilary Putnam, Rudolf Carnap, Saul Kripke
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I think it has nothing to teach which isn't completely trivial
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>>8490563
How come noones written a 'philosophy of science' about something that really matters; like the fact that the peer review system is worse than useless by dint of the fact that its 'science by consensus'.
See the issue here is that instead of writing how how to do stuff like normal STEM, they write about how *people* are doing stuff. Only problem is, they're autists who don't understand people.
They should probably just stick to doing stuff and stay in their lane.
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>every thing must go
>james ladyman
>ladyman
What about your last name bro? That shit needs to go.
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Help me /sci/
I want to build an electric generator but have Nickie where to start. And any tutorial I look up yields a small generator. I want to be able to at least power 2 devices at once. And I'd like it to be human powered.
Where do I start? Do I need a permanent magnet?
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>>8490380
*no idea
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What kind of devices are you talking about powering?
Motors and generators are the same materials, so if you had a way to spin the shaft, you can use the electricity produced. So youll need a motor.
Then you are going to need to create a power supply to give your devices a nice smooth and constant voltage. You may need a way to convert to dc depending on your loads. /Diy/ has lots about this stuff
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>>8490401
Maybe a TV and a phone charger.
And not bring rude, but:
doesn't that defeat the purpose making the generator, if I could provide an external power source, why make power?
Is there a way to do it otherwise? I'll ask dyi but I figured I'd ask /sci/ because, you know, science