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Since they've closed down the homework help sticky which I used to love on my old Sythe account, I've decided to offer help to people who have ANY math question at all. Feel free to answer questions if I'm not around to answer them first, because this is all about helping people out :)

BTW, Unb4nn3d is my "official" partner in crime, but if you see a question that's unanswered on this thread and you want to give it a shot, don't hesitate to give a reply! Just don't spam, and answer previously answered questions. This is not for me or Unb4nn3d to get attention; it's to help honest people who are looking for some honest help.

MatthewGor123 said:
My Biography ^_^

Why am I doing this? Meh, I guess I'm a nice person and I like to help people out if I'm good at something...I'm a 15-year old sophomore in high school, and I'm co-captain of my school's math [and tennis] teams at school (I got a 2320 on the SAT's last year), so I think I can use my knowledge to help others out in return for some respect :P

My strongest subjects are geometry and algebra, but I do know a small amount of calculus and number theory.

If you have any questions regarding to any school subject, I can try to help - English, Science, whatever, but I personally prefer math :)

Unb4nn3d said:
My Biography ^_^

-Currently enrolled in Pre-Calculus
-Taking AP Calculus AB in 6-7 weeks

Background:
Name: Alex Menteer
Age: 17
Grade: 11th
Current Class: Pre-Calculus
Experience: Advanced Math since FIRST GRADE

So, I should be in AP Calculus CD right now... but I didn't want to double Math courses my Freshman year.

My Freshman year, I split my head open on the 3rd day of High School (bike accident)
My brother got food poisoning, and my Grandmother died in the next 2 weeks
-I had to see my Grandmother die

Then a within the next year, I had 2 Groin Pulls, and a leg brace put on.
-The leg brace was on for 3 months, and my leg is messed up bad now
-Technical name : Avascular Necrosis of the Femurol Head

Now that you've gotten to know us a bit better, ask us any questions you want!! ^_^

EDIT: If your question is regarding math, please reference: [GUIDE] The Largest Math Guide in History, written entirely by me and Unb4nn3d :D
 
Porman, I took 2 college classes last summer, and 2 more the summer before that...I got an 800 on the math SAT's last summer. In middle school, I finished 3rd in my state for the high school math league (IMLEM), and Freshman year, I finished 17th for all high school students in the MML. So seriously, don't judge me by my age. How about you ask me a question first, then judge me? Obviously I don't know everything, nor do I say I do, but I'm just saying I can try my best. If it's a high school math question, I'm very confident I could help.
 
I posted a question up on a homework help thread somewhere, but now I can't find the thread... I'll edit this post when I find it :P
 
The thread seems to have vanished into thin air. This isn't easy stuff, and I'm older than you and doing advanced maths for my age, but here we go:

Solve the differential equation:

dy/dx = y(x+2y)/x(y+2x) where y=vx where v is a function of x.

I did some working and got stuck on this line (pretty sure all is right up to here):

int[((v+2)/(v+2v^2)) - (1/v)] dv = int[1/x] dx

If you can tell me how to integrate that line up there, then I'd be very happy.
 
Alright, I'm epic fail at integrating differentials well, I do think I have a simmpler equation for your integrating purposes :)

Okay, so from dy/dx = [y(x+2y)]/[x(y+2x)] and y=vx, we can substitute vx for y everywhere on the right side of the equation.

dy/dx = [vx(x+2(vx)]/[x(vx+2x)]
dy/dx = [vx^2(1+2v)]/[x^2(v+2)] <--- I hope this step makes sense, you factor out an x from both the numerator and denominator because you had [vx(x+2vx)] which is equal to vx(x)(1+2v), and same for the denominator.

Factor out the common factor (x^2) from the numerator and denominator and you are left with what I think is a much easier differential to integrate (then again, I'm not 100% sure yet -- I think I'll ask my father tomorrow...when he wakes up...)

dy/dx = v[(1+2v)]/[(v+2)]

Hope I could help, at least a little. Maybe my daddy will be able to integrate it, but I'm not so confident with my integrating skills; I don't want to give you any WRONG information. What I've done to this point is right, though.

EDIT, here is what my grandfather tried to tell me by phone, so I'm going to see if I can rewrite it here; We need to find dv/dx. So, you have:
y = xv
dy/dx = v + x*dv/dx (this step confused me, but I think it's just algebraic integration, I couldn't quite see it)
Therefore, substituting what we already found for dy/dx;
v + x*(dv/dx) = v*[(1+2v)/(v+2)]

x*(dv/dx) = v*[(1+2v)/(v+2)] - v.

And then he decided to stop explaining, because he said I probably don't understand it. GAH. Oh well, I tried my best, and got kinda far. Sorta. He said something about it being separable.
 
dude O.O

i cant get past the equations... my teacher sucks i dont understand a shit
 
I was not being dumb, nor was I being a spammer. I was challenging your mathematical understanding. Anyone who knows anything about math knows that you CANNOT DIVIDE by 0. You were unable to solve the provided equations, and so I feel that you would also be unable to solve any other provided equations.

The debate on whether or not 0 is imaginary is completely different than that of whether or not you can divide by 0, which you can't. Sure, one affects the other, but they are two entirely different mathematical theories.
 
I'm not fucking retarded, I know that 10/0 is undefined - but so did you, and everyone else with half a brain. So please, don't go here trying to get your post count up or to test my knowledge with SPAM that you already knew the answer for. There are plenty of interesting questions revolved around the concept of 0 in the field or arithmetic, such as the value of 0^0 or why the convention that x^0 = 1, or even 0/10. But I knew that YOU knew that 10/0 is undefined, and weren't actually asking for help. So, you're posting stuff that is NOT on-topic, thereby spamming.

If you don't need fucking help, don't fucking ask for it. Kthnxbai.
 
Anything / by 0 is infinity.

E.g 12/2, 2 go's into 12 6 times so the answer is 6.
12/0 0 go's into 12 infinity times, so the answer is ~
 
XeroXeroX, you're wrong - please don't argue here. It's a mathematical convention that the operation 12/0 is undefined. It is, in fact, impossible to define an arithmetic operation that's result is infinity using just the basic 6 operators (division, addition, multiplication, subtraction, exponentiation, radicals). While it is true that 12/x [x<1, x -> 0] approaches infinity, infinity is never reached.

I can give you a formal proof later, if you want.
 
Thanks MatthewGor123, I wish I had a handy grandfather like yours. He's right, to solve the differential equation you need to "separate the variables". I'm still puzzled about how to do the entire question :p But me and my friends will work it out together when my holidays are over. Tell your granddad I say thanks.

dy/dx = v + x*dv/dx

Yeah I did this when I was getting to the line I put in my other post. It's differentiation of y=vx, I believe.
 
It is, in fact, impossible to define an arithmetic operation that's result is infinity using just the basic 6 operators (division, addition, multiplication, subtraction, exponentiation, radicals).
...

6 X &#8734; = &#8734;

...

This also holds for other basic operations..
 
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