/sqt/ - stupid question thread

How many years does it take in your country to get a bachelors degree? Starting to count when you leave the "highschool" equivalent of your country.

Also cows and other farm animals produce exhuberant cuantities of methane, wich has a bigger impact on the atmosfere than CO2

I really suck at vectors, like I know the basic addition and subtraction, and multiplication, but when it's a bit more complicated, I just get lost. Any clear and concise tutorials on youtube that you know of?

Apparently, Mochizuki's developments are going to make Wiles' proof trivial.

Here in Germany it is 3 years although if you fail a lot of classes it can go up by quite a bit.

I know this is sqt but what exactly is your goal here? If you're waiting for every single nationality to answer about their schooling systems you're probably not going to accomplish anything.

Why or why not is nuclear energy a viable, sustainable energy source?

meant to add "currently" to that question

Shouldn't physically demanding jobs be paid more?

Humans have been doing physically demanding work since forever, and are quite good at it. Higher paying jobs, usually require more knowledge to do, and they require more investment, because education is expensive. The market decides how much a job is paid.

Now that that's out of the way, you are absolutely right. The pay that physical workers receive is appalling. They *should* be paid more. They aren't. The world is not perfect. Hopefully someday.

I have the latitude and longitude of a coordinate. For this point, I'm given a distance (in metres) and the angle of which the distance is in wrt. the coordinate. Pic related.

How can I get the latitude and longitude of the endpoint of the distance?

In trying to plot the line with Python and matplotlib, and the only thing I can think of is to get the latitude and longitude of the endpoint and plot the two of them so that matplotlib treats them as a line.

The more people can/will do your job, the less you will be compensated for it. A lot of people can do a lot of physically demanding jobs, but not much else.

If im understanding you right you have one point and from that point you have a line with a distance and an angle.
And now you want to find the end point of the line.

If you are working in 2d coordinates the end point is given by cos(angle between line and latitude)* length as latitude and cos(angle between line and longitude)* length as longitude.

In other coordinate systems you have to use additional transformations.

Its good because theres loadsa uranium, plutonium and thorium hanging around. Also very low CO2 emission. The cost of running the power plant is not very high. Its bad because building the power plant is extremely expensive, and its lifetime has a hard limit (30-50 years, after that the reactor tank will get too damaged). Also retards think that its dangerous, however the PWR design is very safe.

>multiplication
you can't multiply vectors
there are inner products and cross products though

go pick up any intro linear algebra book and work thoroughly through the first few chapters

4 years depending on the career,sometimes 5. Medics get 6 i think, and a year of "social service" which is an unpaid half-time job

>like I know the basic addition and subtraction,
Vectors are just things where this is all you can do! You can also scale, but this just means that you are really dealing with entire lines instead of single points. I can expand upon that last point if you need.

math guy here
does physics ever just click like mathematics? do you ever intuitively "get" stuff?
i'm having to memorize a lot of stuff, but i want to be able to derive these equations and formulae myself
how long does this take?
math never takes me this long and i'm getting frustrated

how would you computer the 72.25 percentile for f(x) = (x+1)/2 ?

-1 < x < 1

What's the difference between subset and proper subset

Why are sets called list of objects, but not list of elements

Could some one answer this for me:

Subset that isn't equal to the set
>set A={a,b,c}
>subset can contain a,b and/or c
>proper subset can't contain a,b and c

A set can be a subset of itself, but a proper subset must have something missing.

Physics is a different kind of thinking than pure mathematics. Like all things, you'll get better with time. You need to practice solving problems, deriving easier principles, and using different tools. Though, I'm not sure what level you're at that you're only memorizing. Even at just calculus-based mechanics/E&M, you can derive pretty much everything from some basic principles/experimental results.

I see. Is there any significance as to why we make that distinction?

Because ∈ does not have this property, for example O has no elements, in particular O∉O. However O⊆O is correct.

The O should be the empty set
>{} or O

shit the O should have a strikethrough

Does anyone even validate their results anymore?

I have discovered Article A made by Group 1 based on combining the results of their earlier Article B method with new data from another group's Article C was actually botched (tl;dr their processing ruined their data), so my advisor got me to write up a report on that to share with Group 1.

Researching the issue I discovered the original Article B, which was itself based on Article D from yet another group, was also botched in a slightly different way.

This morning I have discovered Article D was botched in itself as well.

It's like an edifice of errors heaped upon errors, how deep do I have to dig to find anything that was done correctly?

Fucking biologists I swear to god.

Also note that most of the errors are on the order of someone apparently fucking up sorting stuff in excel and ruining the order of the samples.

Use O or O instead.

Newfags can't [math]\emptyset[/math].

I see the problem. Veeky Forums doesn't accept Scandinavian letters.

Guess we have to stick to [math]\emptyset[/math] and [math]\varnothing[/math], then.

Why does the Cartesian product on n sets define a set of functions?

I thought a function was a set of ordered pairs, not just a single n-tuple

why cant i calculate zeros of functions when theyre negative correctly?

-1 is supposed to be a zero of [math]x^3-3x^2+4[/math] but i get 6, not zero

[math]
-1^3 = -1 \\
3 \times -1^2 = -3 \\
so -1 -(-3)+4 = 6
[/math]

Usually a Cartesian product over an arbitrary family [math]\{A_i\}[/math] is defined to be the set of families (which are functions) [math]\{a_i\}[/math] such that [math]a_i \in A_i[/math] for every [math]i \in I[/math].

3 (-1)^2=3

oh thanks,

part c
I get f = 3mg

because f = mv^2 /r = mgcos@
kinetic energy = 1/2 r f
right??

so then using conservation of energy
mgr - (-1/2 mgr) = 1/2 r f
3/2 mgr = 1/2 3 f
f = 3mg
???

>3/2 mgr = 1/2 3 f
is a typo

Mates, there's this problem in arithmetic sequence, says "Add all numbers

The greatest multiple of 7

I still don't get it... guess I'm a brainlet. Off to off myself...

Can [math]n(n^2-25n+152)=272[/math]be solved simply or am I fucked? Literally spent 45 minutes of my life getting to this "solution", just to find out I can't solve it. I want to kill myself right now.

Multiply 7 by 285. You get something less than 2000.
Multiply 7 by 286. You get something more than 2000.

Now think about it like this. 11/3 = 3.something
3 = 3*1, 6 = 3*2, 9 = 3*3 are the multiples of 3 less than 11 (3 numbers total). Same thing.

[math]272 = 17\cdot 2^4[/math]. All the roots are integers.

Should I understand/study logic before I attempt math? I've never been exceptional at mathematics and always feel I've missed something along the way at my foundation that was never taught be me in public ed,countless math problems can be done and I still don't understand,I just do it and the only thing I understand is my way of thinking needs to change.

use the cubic formula senpai

give more information about your current / desired knowledge, and the stage of your education (hs / freshman / sophomore, in math / engineering / other)

Current: I only got to algebra and never reach further than that or rather I never had the change to.
Desire: I wanted to get better at mathematics so In turn I could get better at programming and seeing as logic follows them both to the core I thought logic would be a good choice to start.
Stage of ed.: In Community college but havent taking any generals yet and just picking up workplace skills.

you don't need a significant logic foundation for the kind of math you want to learn
all you need is to develop very weak geometric intuition and practice a lot

that said, you do need to learn very basic logic as in truth tables, quantifiers and so on

Why do people complicate these things? You learn to be good at programming by actually programming and picking up the necessary math/logic as you go along. The benefits of simply allotting the time to doing it, far outweigh the perceived advantages of losing the time by going the long way around.

Just go ahead and do it. You dont "need it", but it isn't that hard and should help clarify your thinking. The first two chapters of "how to prove it" are a good resource for learning this.

>get better at programming and seeing as logic follows them both to the core
If you're interested in functional programming languages then you could read up on constructive logic and type theory, if want to go that deep into the rabbit hole. Robert Harper's PFPL could serve as some introduction that's not all that scary: cs.cmu.edu/~rwh/pfpl/2nded.pdf

Just learn a functional programming language like Lisp or Haskell, it will make you way better at programming than any kind of math ever will.

What are some places to find textbooks?

Trying to cut back on costs by just pirating rather than renting, but having trouble finding the most recent editions on textbook sites I usually use.

I can probably get away with the 9th edition of this one, but can't hurt to look a little harder eh?

gen.lib.rus.ec/

Can anyone explain to me why Godel's completeness and incompleteness theorem don't contradict each other? Model theory makes my head spin.

Do I go into a Physics program or an Engineering program?

Googling it gives me forum posts made by 12 year olds and universities shilling their programs.

I want the COLD. HARD. FACTS.

I want to use my physics and mathematical skills to solve real-world problems and get paid to do it.

Find the number that is 72.25 % between -1 and 1, and evaluate the function at that value

I was in the same boat as you, until I decided I will just pick engineering. From what people have told me here, and from what I've read, chances of getting a job as a physicist with a physics degree (meaning you actually get to work in the physics field) are demoralising. A lot of physicists end up working elsewhere, finance or some shit. That's why I personally decided I will pick engineering.

>AFAIK

Do you believe that maybe people in academia who find data refuting aspects of 'catastrophic man-made climate change' might find it hard or professionally dangerous to publish, and that might be affecting the 'consensus'?

"prove by induction"
h-how do I even express that in maths
I don't even know what happens when that sequences passes n=8.
Does it go like, 7.8, 8.9, 9.10 or something?

I am complete garbage when it comes to trigonometry, how the fuck do I memorize all the formulas? Most of the time I can't even remember what the hell I should even do... I learn maths by logic, obviously learning how to derive a formula has helped me immensely, but holy fuck, you can't simply derive trig. formulas, not that I know off. HILFE

You can derive all trigonometric identities by Euler's formula- That is:
e^(ix)=cos(x)+i*sin(x)

Ewwww. Euler's. Hated that so much in HS

I've found that if I forget anything, it's useful to remember that:
>sin starts at 0 and goes to 1
>cos starts at 1 and goes to 0
Pretty much any easy trig question just needs you to remember that.

You're not wrong, that question is vague af.

Maybe the general form is n +(n+1)/10?

I thought so, but then when I tried what should have been a not-very-intelligent although surefire proof (see if adding the next element in the series to the predictive equation is equal to the predictive equation with all n replaced by n+1), I still ended up with a contradiction.

(n+1)(n+2)(n+3)/3 = n(n+1)(n+2)/3 + n+1+(n+2)/10
>a short while of math later
n(n+1)(n+2)/3 + (n+1)(n+2) = n(n+1)(n+2)/3 + n+1+(n+2)/10
Clearly there's a problem with the implied (n+1)(n+2) = n+1+(n+2)/10

they're multiplication dots, not decimals

what are you guys doing?

its the sum of k(k+1) from k=1 to n

and n(n+1)(n+2)/3 on the other

you check n=1 and you get 2 on both sides

you assume the inductive hypothesis for n

It's the only time in this entire course that dots have been used, even elsewhere in the same question it's just written as n(n+1) where multiplication is meant, not n.(n+1)

you should tell your professor/whoever wrote the textbook to step up their latex game then

you should be able to plug in n=1 by yourself to get "1.2" = 2 and guess that it should be multiplication

>to solve real-world problems and get paid to do it
The answer is fucking obvious and it's engineering.

Well, too late for that now!
Thanks for the tip though, never even passed my mind that it could be a really bad latex fuckup.

In a deck of 52 cards how many different 5 card hands are there that contain at least 3 queens?

Help i feel retarded and i cant remember highschool

3 queens: 4C3*48C2
4 queens: 48C1
Then add them up to get your answer.

Thank you

Last question
In how many ways can a 5-member student council be chosen from 9 boys and 8 girls if there must be at most 3 of each gender on the student council

anybody have a good book recommendation for circuit analysis?I'm taking aclass on this this fall but im reading the book reviews for this book

amazon.com/Engineering-Circuit-Analysis-William-Hayt/dp/0073529575/ref=sr_1_1?s=books&ie=UTF8&qid=1470369817&sr=1-1&keywords=hayt engineering circuit#customerReviews

and they're pretty bad. Need something that has more than work problems.

3C9*2C8 + 2C9*3C8

do you mean
(9C3*8C2) + (9C2*8C3)

Yes, I did.
>the city of me

> It's the only time in this entire course that dots have been used, even elsewhere in the same question it's just written as n(n+1) where multiplication is meant, not n.(n+1)
Multiplication doesn't need a symbol if the operands are variables or parenthesised expressions. But for two integers, you need the dot to distinguish 2.3 from 23.

Completeness just says that every consistent theory (can't prove everything from it) has a model.

Incompleteness says that no (sufficiently powerful) decidable set of axioms can decide every sentence (i.e. prove either A or prove ~A).

In any particular model, every sentence is either true or false, but that doesn't mean you can prove it. So AC (or Con(ZF) etc) is either true or false in any model of ZF, but you can never prove it from the axioms alone.

NZ here, anyone know if it's possible to do level 2 reassessments in level 3? I fucked up bad in Math

You don't need Euler's formula for the basic ones, think

cos = x/r
sin = y/r
tan = y/x
etc.
(or SOHCAHTOA if you prefer)

Then just use r^2 = x^2 + y^2.

Can someone explain how an induction motor works? I keep reading about how they work but the words never seem to stick.

I'm relearning Biology. How best can I hammer all the knowledge into my head so that I don't forget it in a few weeks?

I am tired of seeing people who say this. Just stop lying to yourself. You're learning, not relearning.

Okay, I'm learning Biology. How best can I remember the material?

Gravitational induction?

Sorry pentium 4 I am used to use on psychiatry would take years to do one good simulation...

But I can explain if you get me enought learning computer, but I want to be able to unplug it personally