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Archived threads in /sci/ - Science & Math - 27. page
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File: 1460143222655.jpg (19 KB, 320x240) Image search: [iqdb] [SauceNao] [Google]
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I'm curious if cancer is still at the same fatality/ diagnosis rates as it was centuries ago. Everytime I hear someone was taken away because of cancer, I can't help but wonder if it's just a natural human phenomenon, or is it a product of modern times.
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I dont mean modernization, btw, is what caused it. But rather, if we have in someway increased its rate
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longer average lifespan and more exposure to carcinogens in daily life so obviously higher diagnosis rate today. why is this even a thread. jesus
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>>8516323
>more exposure to carcinogens in daily life
Okay, so I wasn't being paranoid in thinking this, then. How does one go about reducing these things anyway? Just setting yourself on a lone island for the rest of your life? I doubt the sun gives enough chance of causing cancer, especially if you're not in direct exposure of it all day

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What're some /sci/ approved science experiments I can do at home that aren't for brainlets, other than engineering stuff.
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Home-made crystals. I don't have the image but someone here surely might have it.
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>>8516291
Inb4 he posts the one that makes poisonous gas and kills OP. Back to >>>/b/

Try finding the charge on the electron with oil drops
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Decarb the weed with your lighter lol smoke weed 420 later nerds

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Quick question: Let's say a fly flew into a car and didn't land, but continued to hover in one place. And the car begins to move, what happens to the fly?
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relative to the car, it would move towards the back.

relative to the ground it would remain where it is.
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>>8516247
>Let's say a fly flew into a car and didn't land, but continued to hover in one place.
I've never seen a fly hover in one place.
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>>8516247
And it probably doesn't understand the. Question?

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>tfw the singularity will happen in 5 years and save me from spiraling depression
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Imagine the look of disappointment on your parents' face when you show up to thanksgiving with a robotic gf.

(I can't wait)
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>>8516149
lmao. try 50
you'll have suicided by then
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>>8516158
> Implying OP doesn't show up with his sex doll anyway.

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How come I can bench press 100 pounds 10 times, but I can't bench press 1000 pounds 1 time? Did I just disprove conservation of energy?
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>>8516092
Looks like it. Step forward and claim your Nobel prize, Mr. Anon!
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>not using a gorilla image
shiggy
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How come a spring can lift a 100 pound weight repeatedly over the course of its lifetime, but never a 1000 pound weight?

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Does anyone know a good rechargeable digital scratch pad that I can buy to save trees and money? I'm in my 3rd year electrical engineering and I use up A LOT of paper for my maths and physics.

P.S. I'm not a conservative.
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>>8515916
why get a scratch pad when you can just get a surface pro? then you can get a wabbitemu calc emulator and keep all your notes on onenote
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>>8515928
I can't afford it lol, my budget is around $100 >> File: b2d.png (97 KB, 746x545) Image search: [iqdb] [SauceNao] [Google] 97 KB, 746x545 >>8515930 >my budget is around$100
Then just get a generic Android tablet like the Kindle Fire or the Asus Zenpad

Or you could get 2500 sheets of Roaring Spring Paper Products Engineer Calculation Filler™ paper. Your precious electronics and the electrical systems you will build are less eco-friendly than current forestry practices.

>I'm in my 3rd year electrical engineering
>P.S. I'm not a conservative.
>"environmental conservation = US political conservative"
you could save paper AND electronics by dropping out of the program, dipshit

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okay faggots let's build an iron man armor.
i'll start
>8 litre tanks for jet fuel spread on the back and in the boots
>armor plating made out of titanium and alluminum alloy mixed with ceramics spread on top of graphene sheets
>hybrid electric and kerosene jet engine on the back and on the boots
>parachute for safety

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>>8515911
Just one question. Is there any like sexy masturbation stuff happening to your penis while you in that suit? And where would your cum go? Do you just shoot it at your enemies?
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>>8515919
it's not forbidden as far as i know, this is a /sci/ group project. if you want to stick a fleshlight in there go ahead m8
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my turn
>latest and most powerful software
>motion capture suit
>expertly crafted models
>expensive cameras
>green sheet
>2 well payed gfx artists

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>>8515878
http://www.wolframalpha.com/widgets/view.jsp?id=4a882b546a46d492fdbf3679cbac49d4
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>>8515878
Nah mank, triangles are the alpha shape.
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>>8515878
>>8515914
Square is the best because it allows us to make grids.

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Hmm
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>not playing 07
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>>8515851
I have over 10 mil on my rs account.
Get on my level noobs.
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>>8515885
I had about 12mil in items, faggot. That was before I was banned for macro using. Happened 1 month ago, I still cry every night.

Help: I need help correcting my problems. Can anyone give me a thorough explanation of what I did wrong in these? Please and Thank you.
>>
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>>8515769
Well, for starters stop being lazy and actually scan your shit for better comprehension.
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Holy fug, OP. A 39 in Algebra II?
Go to tutoring.

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Should we allow non-scientists to verify our work? Is peer review as bad as allowing police to investigate the crimes of their fellow officers?
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>>8515752
that picture is bullshit.
other scientists are peer reviewing you as a scientist in the same way that the police is investigating you as a police officer
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>>8515784
also to answer your question, or at least give you acounter question.
who, other than scientists would be competent enough to peer review a scientist?
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How is a scientifically illiterate person going to verify science research is done correctly? You don't bring in a random guy with no electrical experience to inspect an electricians work.

With peer review you have people who know their shit from other universities checking over research. This is similar to how independent investigations of police misconduct are supposed to be handled. You get cops from LA to investigate cops from NYC so nobody is covering for their bros.

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How do I prove this?
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analytically
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>>8515757
What does that mean?
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>>8515744
It's false

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Hello there,

I'm not from a country where many mathematics are taught but I recently moved to North America, I am 26 and have been wondering how to master trigonometric identities. No specific difficulty level. What is the trick? Forgive me

Thank you.
>>
you have to go de vuelta a tu puto pais
also, just apply: $e^{i \theta} = cos( \theta )+i \space sin( \theta )$
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>>8515677

Can you explain how this works in detail? Are you saying that this identity can be applied to any scenario? Most of my research suggests a "Left Side, Right Side" method.
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>>8515658
let the unit vector in the x axis (1, 0) be
⌈1⌉
⌊0⌋
and the unit (basis) vector in the y direction be
⌈0⌉
⌊1⌋
Then the matrix A(ϕ) that rotates (counter clockwise) a vector by ϕ will take the unit vector in x direction to
⌈cos(ϕ)⌉
⌊sin (ϕ)⌋
and takes the y vector to
⌈-sin(ϕ)⌉
⌊cos(ϕ)⌋
Thus A(ϕ) equals
⌈cos(ϕ) -sin(ϕ)⌉
⌊sin (ϕ) cos(ϕ)⌋
Therefore the unit vector at θ to the x axis will be rotated to θ+ϕ after applying...

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Explain why this isn't possible.
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>>8515620
Carbon 14
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>>8515621
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>>8515620

>must have been homosexuals

Topkek.

>Helped gather fruit and used their incredible strength to turn lemons into delicious, fresh lemonade.

Give me line and verse.

There were 3 engine jet airliners with 2 wing engines and 1 rear engine like this, but never an airliner with 2 rear engines and 2 wing engines. 3 engine jets with 1 engine in the tail have all stopped being produced because of safety concerns over an engine in the tail where control surfaces are, but airliners with 2 rear engines are still produced since neither engine is actually in the tail. So why did nobody ever make a plane with 2 rear and 2 wing engines
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>>8515582
You don't want the rear engines to ingest the exhaust from the wing engines. Also debris from wing engines risk destroying the rear engines.
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>3 engine jets with 1 engine in the tail have all stopped being produced because of safety concerns over an engine in the tail

lol no, Its because of ETOPS
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>>8515717
This, hard to reach, hard to fix, harder to pay for.

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recommend me your best Deep / Philosophical podcasts , you know what i mean , something that makes me question everything about my or rather our existence.

>inb4: philosophy isn`t a science therefore wrong board
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>>8515508
>podcasts

It's like reading popsci and wanting to get enlightened.

Philosophy textbooks for High-Schools are a good choice if you want to have a general view of the history, movements, technical terms and philosophies.

Then it depends on what interests you. Politics ? Ethnics ? Art ? Metaphysics ? Epistemology ? Modern philosophy ?

The most " question everything about my or rather our existence" philosopher out there might be Schopenhauer, albeit...
>>
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>>8515529
I request one "Politics ?", please.
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>>8515529
>Schopenhauer
ty familia

>It's like reading popsci and wanting to get enlightened.

just need something to listen at work

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Pick a door.
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numero 2
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>>8515405
2
>>
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Do you change?

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If evolution is real, then how come humans didn't evolve to be able to eat raw meat? Surely millions of hunters were killed after eating the raw meat of their prey, and thus humans would have started evolving to be able to eat it.

This is checkmate to anyone who believes in evolution.
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This is some of the lowest tier bait ever, anyone who does not understand this, or falls for this. should put a gun in their mouth.
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>>8515390

never heard of sushi?
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>>8515413
Not an argument.

>>8515415
I meant raw meat we can't eat.

As of right now, I cannot afford a 4 year degree. I am working 2 jobs and helping my dad pay off some bills and I am paying some bills myself. I was a CS major, but had to stop going to college for family and some depression reasons. Thinking about getting my Associate Degree in Web Developing/programming instead. My main goal is to go into Web Developing. I already know HTML and CSS and I am learning JavaScript on my free time and will later learn PHP. I have begineer Java skills, but will learn more later on. I am a great self learner. Do I actually need a 4 year degree? I...
>>
1. make a functional website
2. pick up freelancing jobs
3. when they ask you how good you are at building websites, link them 1. and tell them "i made dis"
4. get money
>>
Not a degree. You just need to know how to read other people's code on github.
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>>8515387
What the fuck does being a Web Developer have to do with science and math? >>>/g/tfo

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For a mathematical group to have associativity, is it required there be at least 3 numbers in that group?

Seriously can't find this anywhere
>>
IE for a*(b*c) = (a*b)*c to be true is it required there be 3 different members in a group?
>>
>>8515380
No. ({0}, +) is a group, although it's not particularly interesting to say that 0+(0+0) = (0+0)+0
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>>8515394
How am I supposed to infer associativity from it if the definition uses 3 differently marked members (a,b,c)? Why can I just put the same number as all of them

Obviously it's astronomically unlikely, but can another planet or celestial object exist in our solar system - on the opposite side of the sun, without us knowing it? Either
> mirroring Earth's orbit
Or
> slower/faster than Earth's orbit so it disappears and reappars, ie. last seen 1400s, will reappear in 2017

I don't know shit about astronomy and it's been bugging me
>>
it would be noticed through its gravitational influence
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>>8515374
>without us knowing it?
Nope, we would have been able to detect perturbations in the orbit of other planets/moon also I think the Lagrangian points would be different if there was another planet shadowing us.
>>
Short answer no. Longer answer it would not be possible for such a massive object to be 'hidden' as it would interact with other objects in the solar system due to its gravitational effect.

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This book is a good reference but let me tell you what its really good for. You have taken all the lower division courses. You have taken that "transition to proof writing" class in number theory, or linear algebra, or logic, or discrete math, or whatever they do at your institution of higher learning. You can tell a contrapositive from a proof by contradiction. You can explain to your grandma why there are more real numbers than rationals. Now its time to get serious.

Get this book. Start at page one. Read until you come to the word Theorem. Do not read the...
>>
No but really. Anyone who passes you an analysis book that does not say the words metric space, and have the chapter on topology before the chapter on limits is doing you no favors. You need to know what compactness is when you get out of an analysis course. And it's lunacy to start talking about differentiation without it. It's possible, sure, but it's a waste of time and energy. To say a continuous function is one where the inverse image of open sets is open is way cooler than that epsilon delta stuff. Then you prove the epsilon delta thing as a theorem. Hows...
>>
Nice pasta
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>>8515300
>tfw this shit actually got spammed with upvotes on Amazon

Come here to talk about the true model of the cell, based on water structuring
>>
No one cares nerd
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>>8515233
>>
>>8515233

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What will the sun's final kill count be?
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>>8515197
4
>>
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>>8515244

this

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b = a
ab = a^2
a^2 + ab = a^2 +a^2
a^2 + ab = 2a^2
a^2 + ab - 2ab = 2a^2 - 2ab
a^2 - ab = 2a^2 - 2ab
1(a^2 - ab) = 2(a^2 - ab)
1 = 2
Explain
>Pro tip, you can't.
>>
>>8515180
a^2-ab=a^2-a^2=0
(a^2-ab)/(a^2-ab)=0/0
a^2-ab)=/=2(a^2-ab)
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>>8515180
> 1(a^2 - ab) = 2(a^2 - ab)
i.e. 1x0 = 2x0
> 1 = 2
Does not follow.

0/10. Not even /b/-tier.
>>
>>8515180
a*a is no the same as a^2 stupid retarded brainlet

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Anyone here ever joined a Maths Olympiad competition or any other well known maths competition? I just got selected to represent my university for an inter-university competition. I want to hear your thoughts and experiences.
>>
>>8515176
bumping for interest
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>>8515176
I have been selected for the "Concours Général" in France, the exam was as a level completely different from what i have seen before.

The fun fact is that we had 6 houre to do it but it wasn't even made to be finished
>>
>>8515176
you will get raped

Ready your palm branches my fellow /sci/entists, for this /mathgenius/ has returned.

I have scored a 98 on my second diffeq midterm. Save your applause. I just thought I would let everyone know.
>>
i'll fart in ur fucking face u gassed up cunt
>>
>>8515075

>diffeq

you're still doing basic arithmetic

learn real math pleb
>>
>>8515075
>differential equations
>lower division math

fucking jej, any monkey can memorize a couple methods of solving algebraic equations and ace a class like that.

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http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.115.260403
(excuse my lack of familiarity with physics nomenclature)
In the current version of this experiment (without the currently impossible pass-through measurement devices), physicists say that the light does not decide to be a particle or a wave until measured. But what happens if we somehow measure it before forcing it to be a particle or a wave? Will it always be a particle because there's no uncertainty at the point I've placed the measurement devices? If so, is there a way to introduce uncertainty?
Sorry...
>>
>>
>>8515029
What does "particle/wave detector" mean?

How does it detect? Is it a double slit?
>>
>>8515759
I have no idea how the detector that would allow it to pass through would work. As for the other detectors used in this experiment, the measurement devices at the end result in a similar pattern to the double slit when it's a wave, which is how they distinguish between wave and particle.
Let's say that for the purpose of this thought experiment, it uses the same mechanism but lets the particle pass through.

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How can I approximate someone's intelligence without directly putting them to the test?

I am attracted to girls who are smarter than me but I'm pretty smart so such girls are hard to find.

Also, I'm ugly so any smart educated hot girls are out of my league.

I'd have no trouble going for an ugly girl but then we would have ugly children, so what's the point? Shit sucks.

So my only option is a hot smart girl who is uneducated (think Christian community girls). I know some happen to be smart. But how does one go about figuring...
>>
>>8515023
go meet people.

If you like a girl you meet, date her.

If you don't like her after some time with that, break up.

Repeat until you're happy with someone. You don't pick a girl based on a formula or how ugly your kids might be.
>>
>Also, I'm ugly so any smart educated hot girls are out of my league.
you shouldn't really think in terms of league, assertiveness is way more important than attractiveness when it comes to seducing women. I think most of us have seen hot chicks with average or ugly dudes. At worst you'll get rejected, but it's still good training.
As for detecting smart people, I think the easiest way is to check if they understand sarcasm (don't do it too soon though, it's hard to detect sarcasm when you don't know whether...
>>
>>8515023
Talk to her for half an hour.

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>In a HS Calc 1 class
>Teacher doesn't teach with book, uses her own notes and stuff
>Chapter is integration
>"This shit is so easy"
>"Hmm.. Maybe I should look inside a legit math textbook for once and see if I can follow the more formal stuff"
>Go to the integration chapter in Spivak's
>Can't understand

Am I...
>>
>>8515017
Turning immediately to the integration chapter and then complaining you don't understand the notation kind of go hand in hand. If you read it from the beginning (and the textbook isn't shit tier), all the notation the author uses will be defined, especially for an introductory text. As for the proofs, if you're not trying to understand them you're not going to understand them. I don't know what else to tell you.
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>>8515027
I just kind of assumed that the topic could be read over in the textbook separate from the rest if you already have an understanding of it and the previous topics covered. I guess it would've been smarter to follow along through the book from the very beginning. Looking at it just intimidated me greatly since I'd like to be a math major (actuarial mathematics in particular)

Fortunately, I'm going to retake Calc 1 in college because of how shitty my HS calc class was, I'd like to get a better...
>>
>>8515017
Because you're a retarded high school baby who has only been exposed to basic algebra so far. Reading formal mathematics is a skill that you need to practice. So, yes, spend a bit of time trying to understand Spivak. Make sure you fully understand every single sentence and word and how each step follows logically from the previous. If you come across a term or a piece of notation you don't understand, flip back to the part of the book where he explains it. Every term has a precise definition.

It's...