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/sci/ - Science, Technology, Engineering, and Mathematics

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HELP!! Anonymous 17/05/01(Mon)00:01 No. 16490 ID: e202d0 [Reply]
16490

File 149358971341.png - (34.32KB , 769x733 , 1479011986675.png )

Can someone explain a quadratic equation in a way that makes it more intuitively understandable? My algebra teacher just rambles endlessly about unrelated shit.


3 posts and 1 image omitted. Click Reply to view.
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Anonymous 20/05/19(Tue)20:48 No. 16923 ID: fc6c5f

>>16922
sorry, in the 1st example I wrote (f(x)=0 when x=1)
x=-1


>>
Anonymous 20/05/20(Wed)18:41 No. 16924 ID: be6f8f

Whoa, I just saw this the other day while I was looking for a comment I made in the seventh page.

>>16922
Dude, you're responding to a question from three years ago. I'm sure OP has since learned what a quadratic equation is, or they don't care anymore.

Your method seems a tad too complex for my liking. Why do you think it's better than simply remembering
x = (-b (+/-)sqrt(b^2 - 4*a*c))/(2*a)
? That's a single formula that solves any quadratic equation in a single step.


>>
Anonymous 24/01/02(Tue)01:28 No. 18705 ID: fb47ff
18705

File 170415529713.gif - (311.20KB , 300x300 , tumblr_lxggprahmL1qfg7o3o1_400.gif )

>>16924
>>16490
Now it's even farther in the future and the quadratic formula hasn't changed a bit. I hope OP is ok.




Anonymous 23/11/11(Sat)21:39 No. 18699 ID: 5fa0eb [Reply]
18699

File 169973519563.jpg - (1.31MB , 3000x2389 , 1697987336291061.jpg )

I have forgotten everything I learned about physics in secondary school.
Why does this not work?
https://odysee.com/@DrAutonomy:f/Free-Light---220v-Free-Energy-Generator-with-Perpetual-Motion-of-Neodymium-Magnets:c


>>
Anonymous 23/12/11(Mon)17:51 No. 18701 ID: be6f8f

https://en.wikipedia.org/wiki/Magnet_motor#Working_principle

>The force between permanent magnets is conservative as the magnetic field follows a potential, so that there is no work done over a closed cycle.

In other words, the magnetic field is shaped like a valley. You can extract a bit of energy from it by falling into the valley (energy you stored when you climbed out of the valley previously), but if you're simple circling the valley without ever reaching the bottom then you're not extracting energy, and certainly not an infinite amount of energy.




Cave Johnson 23/12/09(Sat)15:47 No. 18700 ID: d1e269 [Reply]
18700

File 170213323551.jpg - (103.64KB , 500x664 , 993a6dc32a92c566d48b82fbf946000d.jpg )

The prime movement of humanity is superheated plasma of cosmic background radiation, puppet stringing along blood pressure and the 4th-dimensional potential of water consumption.

Horsepower alone can be derived as a dimension of life through pressure dynamics alone.

But my real secret is most of my family has been saved by surgery and medical science. I never touch a hospital bed. I have other secrets.

I am just happy to escape as a Zen monk on fire.



I am Ra. We are not happy with our Venusian scientist claiming he is not helped by any here for this. :)



All are free to share in my "not a cult." Test subjects may apply for their food allowances per day. And a share of life insurance for their families.
Message too long. Click here to view the full text.




sounds mathematical Anonymous 19/07/09(Tue)23:45 No. 16796 ID: 407f46 [Reply]
16796

File 15627087474.jpg - (37.19KB , 640x360 , 3dkmmfq2co731.jpg )

sounds that were created using mathematical formulas affect a person ?

https://www.youtube.com/watch?time_continue=1651&v=q9pAv_f00CA

https://www.youtube.com/watch?v=juY1C68goWg&t=1261s

https://www.youtube.com/watch?v=2bwiO-Beuwo


4 posts omitted. Click Reply to view.
>>
Anonymous 19/08/15(Thu)13:11 No. 16848 ID: 830de8

>>16847
* waves


>>
Anonymous 19/10/26(Sat)18:19 No. 16868 ID: 5454f2

>>16796
Yeah I was doing some reading about this.
The CIA released some documents about their investigation into the Monroe Institute's Gateway Experience and found that they could not reproduce the effects of the hypnotic tones while using vacuum tubes or some such, so that they concluded the hypnotic effects were caused by the electromagnetic waves in the headphones and not the acoustic waves of the recording. Of course, any neurotransmitters in your brain are going to resonate with some specific frequency, so it's no surprise to me if sound waves can effect cognition.




RMS "Approves" GRSecurity GPL violation, says "may" be Anonymous 23/09/06(Wed)13:15 No. 18687 ID: 5947a7 [Reply]
18687

File 169399895772.png - (105.89KB , 866x765 , ss3.png )

>From: Richard Stallman
>To:
>Sent: Tuesday, September 5, 2023 at 08:59:56 PM EDT
>Subject: Re: Could you please sue GRSecurity.
>
>
>[[[ To any NSA and FBI agents reading my email: please consider ]]]
>[[[ whether defending the US Constitution against all enemies, ]]]
>[[[ foreign or domestic, requires you to follow Snowden's example. ]]]
>
>
> > RMS: please. You sued Cisco.
> > Yet this is allowed? (they violate the copyright on your GCC, in addition to the Linux Kernel)
>
>
Message too long. Click here to view the full text.


>>
Anonymous 23/09/06(Wed)13:47 No. 18688 ID: 5947a7

And, Yes I am a lawyer.
Yes GRSecurity is contravening the "u can't put any additional restrictions not mentioned in the text of this license" clause of the GPL; vs both the Linux Kernel and the GCC "plugins" they distribute subject to their(GRSecurity's) "no redistribution" clause (which has been effective: the source has not leaked: GRSecurity has made it's patches to the linux kernel and GCC proprietary)

The GCC "plugins" are non-separable derivative works, just as their linux-kernel patches are non-separable derivative works. They only work regarding the parent work.

Don't believe me: read the real player case then. Go on. Read it. If you even make some 3rd party program that messes with the look of the other program you can be violating the copyright on the other program. Go read the case. There are others but when I tell you people you just say "DURR WHY NOT JUST DISTRIBUTe A DiFF and GeT aRoUnD the GpL thaT wAy"

Why won't RMS sue? Because he has women lawyers surrounding him who don't want to do shit. That's actually their job: to dissuade RMS etc from taking any Copyright action and upsetting the "GPL-as-effectivly-BSD-Licensed" status-quoe that emerged.

The only courageous one was Bruce Perens who fought abit of the good fight.
Note: ANY of these federal copyright lawsuits would cost probably half-a-million or more for the Copyright owner to prosecute.
RMS's foundation doesn't want to do it.
GPL rots in it's grave.


>>
Anonymous 23/09/22(Fri)16:27 No. 18690 ID: be6f8f

I have no idea about the details, but I do know one thing: the GPL is cancer that needs to go away. If companies are starting to test the waters then let them. If the FSF doesn't want to pursue legal action then let them. Hopefully people will stop taking the GPL seriously. I'll dance on its conceptual grave the day that happens.

And yeah, obviously the FSF has nothing to do with the Linux Foundation.


>>
Anonymous 23/10/20(Fri)10:07 No. 18691 ID: ae5046
18691

File 169778927024.gif - (81.38KB , 269x266 , meifang.gif )

>>18688
>Why won't RMS sue? Because he has women lawyers surrounding him who don't want to do shit. That's actually their job: to dissuade RMS etc from taking any Copyright action and upsetting the "GPL-as-effectivly-BSD-Licensed" status-quoe that emerged.
Good!

>>18690
>I have no idea about the details, but I do know one thing: the GPL is cancer that needs to go away. If companies are starting to test the waters then let them. If the FSF doesn't want to pursue legal action then let them. Hopefully people will stop taking the GPL seriously. I'll dance on its conceptual grave the day that happens.
Me too. Picrel (for both of my replies).

Thing is that Stallman is like oblivious of hardware manufacturers. Raspberry Pi and Audrino are nice hobbies. But then there's non-computers such as synths. Korg's Montron and Monotribe are moddable. Those who mod their own synths are probably the least insufferable people there is. BUT, if you allow for modding that voids the warranty - you will sell more hardware. Basic tools to actually do the modding. And kits to replace it when someone was a huge faggot and ran a soldering iron trough a mainboard.




Prime test Anonymous 22/02/17(Thu)19:25 No. 18131 ID: f85074 [Reply]
18131

File 164512235712.jpg - (3.32KB , 119x122 , download.jpg )

Today one of my recurring dream characters named Jennifer Zemblini gave me a prime number test that correctly validated the first few hundred prime numbers in under 3 seconds using C# code I wrote to validate her primality test!

I wanted to share the primality test with you all now.

It uses only simple division, addition and subtraction. And three variables called n, A and B.

n is defined as the number being tested for primeness. A0 is n-2 and B0 is 2.

Then apply this procedure: Divide A by B, if it is not a clean division, meaning there is a remainder, add one to B and subtract one from A, and repeat this step until B approaches one-half of n.

If A can never divide evenly into B then n is prime.

For example with n=9, which is not prime: A = 9-2. B =2. 7/2 is not even. 6/3 does evenly divide with result 2. And 3 is a factor of 9 also.

But for a prime like 13: 11/2... 10/3... 9/4... 8/5... 7/6... None of these divide cleanly with no remainder, therefore 13 is prime.
Message too long. Click here to view the full text.


4 posts and 1 image omitted. Click Reply to view.
>>
Anonymous 22/02/21(Mon)05:33 No. 18143 ID: bf7eac

>>18142
>quotient is still zero when dividend = n, thus n % m == (n + m * k) % m for any integer k.
This is an error. I meant to say that the remainder is still zero.


>>
Anonymous 22/06/19(Sun)13:11 No. 18281 ID: e5a2d8

I want to clarify that you don't need to sweap across the entire half of the number. If there are no such A and B before B is greater than sqrt(n). There won't be any at all.
And what you did is just a fancy way to do Euclid primality test by checking the first sqrt(n) numbers if any divide n. Since you are checking if B divides A which is none but n-B
Since for all B, B divides itself
So B divides the sum of n-B and B = n
So you're back with the normal primality test, maybe even worse cause you are wasting time computing n-B.
Your Jennifer is retarded.


>>
Anonymous 23/07/26(Wed)00:04 No. 18683 ID: cbe355

Your primality test is 100% right and there is no exception to it. The only problem is that it's not only inefficient (it has an asymptotic complexity of O(n)) but it is basically testing the divisibility of n by any number in the range (2,n/2).




bank account getting drained from hackers Anonymous 17/07/17(Mon)01:09 No. 16526 ID: 030037 [Reply]
16526

File 150024659115.jpg - (32.55KB , 333x360 , serveimage.jpg )

Theoretically, how fucked up would I be if someone used a keylogger on my machine for a few month and leaked my bank account details (online password, PIN, security questions etc) on the Darkweb?

Not worried at all but I just wonder how good these computer hackers are at clearing accounts. Aren't there limits depending on the level of your account? They definitely can get around I.P alerts when accounts are accessed in different countries.


4 posts and 1 image omitted. Click Reply to view.
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Anonymous 17/11/06(Mon)19:26 No. 16575 ID: 7b1c18

Hackers prefer to target businesses for large transactions, because they know few people have $100,000 lying around, while a huge number of businesses have access to that much credit.


>>
Anonymous 18/04/15(Sun)20:14 No. 16647 ID: a66c44

There is this new satoshi dice address for BTC.
Address is bc1quykuahxrjx6d3h6ga4rkyg0hl5e59tcthqyhw6.

I found this while scanning pastebin

Here are the instructions on how to verify the provably fair roll.
https://codepen.io/anon/pen/vRqPMr?editors=0012


>>
Anonymous 23/06/22(Thu)14:04 No. 18677 ID: 88736e
18677

File 168743544397.jpg - (114.49KB , 1424x1080 , 20230624.jpg )

Let me ponder your enquiry




Anonymous 22/07/21(Thu)13:44 No. 18308 ID: 9ce3c9 [Reply]
18308

File 165840388289.jpg - (9.95KB , 215x235 , Z.jpg )

Science is evil...


8 posts and 4 images omitted. Click Reply to view.
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Anonymous 23/02/18(Sat)03:59 No. 18495 ID: c9d146
18495

File 167668916472.jpg - (963.35KB , 2048x2048 , 2024.jpg )

V/STOL is sexy


>>
Anonymous 23/05/19(Fri)11:55 No. 18512 ID: 88736e
18512

File 168449013988.jpg - (145.65KB , 1200x800 , AI.jpg )

This is the way


>>
Anonymous 23/05/25(Thu)11:43 No. 18515 ID: 88736e
18515

File 168500780447.jpg - (357.45KB , 2048x1152 , 20230528.jpg )

Sunny Day




Request: Post HD images of technology Anonymous 17/10/08(Sun)00:10 No. 16561 ID: 864454 [Reply]
16561

File 150741422126.jpg - (105.64KB , 640x966 , OracleExadataExalogic.jpg )

Hey guys, I recently started a computer science class in college and my networking teacher who is the head of the IT department wants us to impress him with the best personalization of our desktops.

> inb4 impress him with your computer programming skills as opposed to flashy images

No anons, No. The motto that he always repeats is that it's important to be "all rounded". He's seen lots of autist computer geeks who are geniuses at what they do but are pretty much mediocre/shit at nearly everything else in their life (social skills, organisation of themselves, writing CV's).

I would like to show off images that highlight an interest in tech along with high quality photography; so if I may ask you kindly to post your favorite images

> I would to the other chan but those fags banned me since June of this year and my shitty ISP hasn't renewed my "dynamic" I.P. address for 4 months.


6 posts and 2 images omitted. Click Reply to view.
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Anonymous 17/12/01(Fri)08:53 No. 16591 ID: 86f262

personalization of the desktop doesn't sound like a assignment....

if you want to make it personal, you need to take the picture yourself. There is nothing special about a good quality pic from the web.

For offtopic, i second this guy -> >>16570
Offcourse i would choose the ugly powermachine instead of nice looking computer that barely even computes.


>>
Anonymous 22/12/26(Mon)03:26 No. 18423 ID: c9d146

Ask for some photos from James Webb


>>
Anonymous 23/05/24(Wed)11:42 No. 18513 ID: 88736e
18513

File 168492132479.jpg - (2.92MB , 4096x2641 , 20230528.jpg )

Absolute Zero




help me please Anonymous 22/10/14(Fri)16:22 No. 18366 ID: 233623 [Reply]
18366

File 16657573648.jpg - (15.15KB , 320x318 , IMG_20221014_095828_475.jpg )

can't really get the click to solve physics numericals... how do u guys do it? like I understand after seeing the solution but can't do it on my own


>>
Anonymous 23/01/10(Tue)13:06 No. 18440 ID: 8b7613
18440

File 167335240760.png - (80.99KB , 502x336 , Graphic-description-of-tribology-interacting-with-.png )

>>18366
Physics as a subject has three areas to master. First theory, second notation, third is application. You got to get all three to pass and understand and they build on eachother. It seems you're having trouble with application. Start solving easy problems and work your way to harder ones.


>>
The+Red+Barron 23/01/22(Sun)10:36 No. 18473 ID: 7cb4c3

You look the answer up on google and memorize it just like your teacher did


>>
Anonymous 23/01/28(Sat)06:34 No. 18478 ID: c9d146
18478

File 167488406828.jpg - (745.98KB , 1080x5284 , 18.jpg )

Color theory of the physics of light





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