/sci/ - Science & Math

what the f*ck is an ordinal

>>10643899
>it's actually surprising time doesn't move backwards! science is sometimes not intuitive, but it's always right!

>"DO MY HOMEWORK >:( !!!"
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If you ask any question, remember that there is almost no universal notation:
>what constitutes a BAD question
If p divides |G|, show that there exists an element of order p.
>what constitutes a GOOD question
Suppose p is a prime that divides the order of a finite group G. Show that there exists an element of order p.

previous thread: >>10068703

>>10060582
this makes perfect sense...

>"FACT: there exists disjoint sets, A, B, such that [math]m^{*}(A\cup B) < m^{*}(A) + m^{*}(B)[/math]"
why is the axiom of choice still allowed to exist

>"DO MY HOMEWORK PLEEAAASSEE!!!"
- edition
This thread is for questions that don't deserve their own thread.
>give context
>describe your thought process if you're stuck
>try wolframalpha.com and stackexchange.com
>How To Ask Questions The Smart Way http://www.catb.org/~esr/faqs/smart-questions.html

Previous thread: >>10006539

This thread is for questions that don't deserve their own thread.
>give context
>describe your thought process if you're stuck
>try wolframalpha.com and stackexchange.com
>How To Ask Questions The Smart Way http://www.catb.org/~esr/faqs/smart-questions.html

Previous thread: >>9977036

>>9679625
excuse me

consider a quadric defined by [math]X=Z(x^{2})[/math] over [math]\mathbb{R}\text{P}^{1}[/math]. How the heck do I show that this only contains the point [math][0:1][/math]?

>>9648086
please help

what the fuck is a surface integral? i can't for the life of me see this conceptually

>a fortiori

can someone explain to me what the fuck a pullback of multilinear form represents

>>9526732

Why is this shit so difficult? I got an easy A in every math and physics class leading up to this (general physics, statics, E&M, linear, differentials), and this subject is still kicking my ass. I spend 15-20 hours a week on homework and I barely understand it. So far we've covered particle/rigid body kinematics, and relative motion. Does it get any easier with kinetics?

>Proof: Think
>Proof: Obvious
>Proof: Straightforward

is it normal to master a subject, get an A, and then completely forget it within a year?

I'm trying to stay fresh in math but I feel the knowledge fading. I was an above average math undergrad but got a programming job. If I was to go straight into grad school right now I'd be fucked.

what's [math]\mathbb{R}\setminus (0,\infty)[/math]

>>9430733
would someone really do that?

just go ahead and lie on the internet?

>half the class are engineers

Um, excuse me can we have MATH discussion here.

Opinions on Wildberger's new algebraic calculus series? Do you think he can do it?

>>9358038
explain