anonymous
  • anonymous
if a differential equations solution divides by x^2 and the initial condition is a point where x=0, what do you do? (problem: dy/dx=xyy or dy/dx=xy^2)
Mathematics
  • Stacey Warren - Expert brainly.com
Hey! We 've verified this expert answer for you, click below to unlock the details :)
SOLVED
At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga. Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus. Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.
jamiebookeater
  • jamiebookeater
I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!
anonymous
  • anonymous
initial condition is (0,-2)
anonymous
  • anonymous
You can use separation by variables here and then integrate. Once you have y after integration, you can use the initial condition.
anonymous
  • anonymous
i did that, but my solution is y=(-2/x^2)+2 which doesnt technically do through the initial condition

Looking for something else?

Not the answer you are looking for? Search for more explanations.

More answers

anonymous
  • anonymous
i think its a vertical asymptote which... definitely isint the point XD
anonymous
  • anonymous
There's nothing wrong with that equation. After you put it into separable form and solve, you should get,\[\frac{x^2y}{2}+cy+1=0\]Initial condition,\[0-2c+1=0 \rightarrow c=\frac{1}{2}\]
anonymous
  • anonymous
You can then factor out y and rearrange into the form y=y(x).
anonymous
  • anonymous
brb
anonymous
  • anonymous
i got c=2?
anonymous
  • anonymous
When you separated the variable and tried to get y by itself did you include c and also multiply the y by it?
anonymous
  • anonymous
.... -.-
anonymous
  • anonymous
ima try that, how about: y'=1+yy
anonymous
  • anonymous
You can do that problem the same way. I look at it as y' is dy/dx and then separate variables. Make sure when you do though, that the 1 goes with the y^2. So move the entire quantity.
anonymous
  • anonymous
dang, the small things get by me... that should be something like arctany=x+c? so tan(x+c)=y?
anonymous
  • anonymous
that explains why my condition is in radians
anonymous
  • anonymous
Yes.
anonymous
  • anonymous
alright... major confusion... \[y'=(e ^{x-y})\div(1+e ^{x})\]
anonymous
  • anonymous
You want to solve that?
anonymous
  • anonymous
sadly ><
anonymous
  • anonymous
Just pull out the e^(-y) and it becomes separable ;)
anonymous
  • anonymous
asoghaqoeraifoiafauirfhlanihusdfvnnfldanufd
anonymous
  • anonymous
\[e^ydy=\frac{e^x}{1+e^x}dx\]
anonymous
  • anonymous
differential equations are gay -.-
anonymous
  • anonymous
lol
anonymous
  • anonymous
dont tell me any more!!!
anonymous
  • anonymous
tell you what? answers?
anonymous
  • anonymous
yeah.. dont tell me any more lol
anonymous
  • anonymous
no worries :D
anonymous
  • anonymous
I think you have the best icon...if that helps...
anonymous
  • anonymous
hahahaha it was annoyingly hard to make XD
anonymous
  • anonymous
i have a pretty good feeling that your icon is not you... though there is a significant chance that i am wrong given by the circumstances
anonymous
  • anonymous
it could be me, since i look like that
anonymous
  • anonymous
lol, how did your frigging doughnut go?
anonymous
  • anonymous
pretty good, i have a way of doing things when i need help: use the first sentence or line of the help, fail a thousand times before i use the second, so on and so forth. so i used quite a bit, but not all of your help in the process of doing the assignment, and in the end i was flowing through it quite nicely, i compared my results to yours and they were identical, i then compared my results to the assignment and apparently the last couple steps, which i had done by hand, i could take the integral with a calculator... and then later he gave us the hand written answer, so i felt proud that i did it without a calculator... but yeah your help is insanely apreciated
anonymous
  • anonymous
alright im stuck at e^y=ln(1+e^x)+c initial condition is (0,1)
anonymous
  • anonymous
Is that y supposed to be y' (y-prime)?
anonymous
  • anonymous
nope, thats my solution
anonymous
  • anonymous
to the above equation
anonymous
  • anonymous
oh..
anonymous
  • anonymous
Yeah. You're right. Leave it like that too.
anonymous
  • anonymous
but i need to find c
anonymous
  • anonymous
Oh, just plug your numbers in.
anonymous
  • anonymous
\[e=\ln 2 +c \rightarrow c = e- \ln 2\]
anonymous
  • anonymous
any way to do that without a calc?
anonymous
  • anonymous
You mean simplify?
anonymous
  • anonymous
No.
anonymous
  • anonymous
What's wrong with Euler's number? :p
anonymous
  • anonymous
ah god its 1... can you check these real quick?
anonymous
  • anonymous
Check what?
anonymous
  • anonymous
Do you ever sleep?
anonymous
  • anonymous
1 Attachment
anonymous
  • anonymous
not too much anymore lol
anonymous
  • anonymous
I need paper...I've run out...hang on...
anonymous
  • anonymous
but all my work is shown?
anonymous
  • anonymous
I get something different for the first one. Just go to bed and I'll look at it and scan and you can look at it when you get up.
anonymous
  • anonymous
do i have to multiply the c by 2 aswell?
anonymous
  • anonymous
I'll do it here:
anonymous
  • anonymous
my answer doesnt make sense anyways... when i find y' its all weird and quotienty
anonymous
  • anonymous
\[\frac{dy}{dx}=xy^2 \rightarrow y^{-2}dy = x dx \rightarrow -y^{-1}=x+c\]
anonymous
  • anonymous
Your boundary condition is (0,-2), so
anonymous
  • anonymous
x+c or (1/2)xx+c?
anonymous
  • anonymous
\[-2^{-1}=0+c \rightarrow c=-\frac{1}{2}\]
anonymous
  • anonymous
So\[y^{-1}+x=\frac{1}{2} \rightarrow 2+2xy=y \rightarrow y(1-2x)=2 \rightarrow y=\frac{2}{1-2x}\]
anonymous
  • anonymous
waitttt the integral of xdx is (1/2)xx+c though!
anonymous
  • anonymous
Oh crap, I forgot the frigging x. Sorry Arman.
anonymous
  • anonymous
nah dont be sorry, i should hit the sheets tho, i'll probably have more questions tomorrow lol
anonymous
  • anonymous
I still get a different answer to you.
anonymous
  • anonymous
basic differential equations (like these) arent usually part of calc II are they?
anonymous
  • anonymous
Yours is close. I'll work through them - they won't take long - and scan and you can read it in the morning.
anonymous
  • anonymous
different answer?
anonymous
  • anonymous
I'm not sure about the American system.
anonymous
  • anonymous
y=2/(1-x^2)
anonymous
  • anonymous
did you use (0,-2) for the initial whatever?
anonymous
  • anonymous
pellet, I wrote it wrong on my paper. I wrote (0,2). SORRY AGAIN :'(
anonymous
  • anonymous
NOW I get what you got.
anonymous
  • anonymous
>< nah man i hate when ppl tell me sorry
anonymous
  • anonymous
lol XD
anonymous
  • anonymous
my calc teacher, this morning, was like "oh flutter..." *covers mouth*... *whole class starts laughing caus we hear him say pellet sometimes but never the f word so it meant he was really screwed over XD
anonymous
  • anonymous
lol, it's great when that happens. I got the same results as you for the other two. The *only* thing I would do differently is leave \[e-\log 2\]as is, and not use a numerical approximation (in the last one).
anonymous
  • anonymous
thats probably better in the math world, where you need to be precise
anonymous
  • anonymous
Yeah, exactly.
anonymous
  • anonymous
is that prefered in college?
anonymous
  • anonymous
preferred*
anonymous
  • anonymous
Absolutely. You'd only use a numerical approximation for the time you actually need to extract a number. Other than that, we leave it because we may want to do further mathematics on it and we lose information/exactness if we start approximating beforehand.
anonymous
  • anonymous
just like the AP exams lol. i think i asked you before but what are the remaining major math courses after differential eqas and linear algebra (when i say top i mean like... there should be less than 3 "top" ones)
anonymous
  • anonymous
?
anonymous
  • anonymous
Yeah, I really don't know. Your system is different to the system in UK, Australia and Canada. We don't break mathematics up into sections like calculus and then apply a skill level to it. We apply a skill level to ALL of mathematics at particular points and you learn EVERYTHING at a particular level.
anonymous
  • anonymous
oh... well what are the chances that i can attain a college grad level (in math) of mathematical understanding in the next year?
anonymous
  • anonymous
given the rate that i covered calc 1 and 2 within 1.5 months
anonymous
  • anonymous
I'd say you're pretty good.
anonymous
  • anonymous
College grad level in calculus...is that what you're asking?
anonymous
  • anonymous
You have to cover calculus of a complex variable as well. There's also tensor calculus.
anonymous
  • anonymous
not just calculus, but all mathematics, can i attain that sort of knowledge, about 4 or more years of college math in the next 9 months?
anonymous
  • anonymous
complex variable wont be too hard, what is tensor calc??
anonymous
  • anonymous
It *might* take a little longer ;p
anonymous
  • anonymous
They're devices we use to extend scalars, vectors and matrices to higher dimensions.
anonymous
  • anonymous
They're very useful.
anonymous
  • anonymous
http://www.dailymail.co.uk/news/article-1369595/Jacob-Barnett-12-higher-IQ-Einstein-develops-theory-relativity.html
anonymous
  • anonymous
my goal, i am currently 11 years behind
anonymous
  • anonymous
It also depends on what areas you want to focus on in maths. There's discrete mathematics/number theory, mathematical logic, topology, algebra, mathematical statistics,...
anonymous
  • anonymous
Yeah, I'be heard of him. I hope you get there (minus the autism).
anonymous
  • anonymous
*I've*
anonymous
  • anonymous
We 'know' general relativity is wrong - feel like fixing it, Arman?
anonymous
  • anonymous
sounds like a plan
anonymous
  • anonymous
What about bed?
anonymous
  • anonymous
Might be the first step.
anonymous
  • anonymous
oiudhvcapoufimnac
anonymous
  • anonymous
Is that code?
anonymous
  • anonymous
fine -.-
anonymous
  • anonymous
lol
anonymous
  • anonymous
nah, gibberish.... alright my chances of catching up to an ausbergers kid is highly unlikely, but i can at least try to match his pace...
anonymous
  • anonymous
i think... idk. i will win -.-
anonymous
  • anonymous
yeah, that's the right attitude
anonymous
  • anonymous
Just ace your doughnuts.
anonymous
  • anonymous
lol iight gnight yo
anonymous
  • anonymous
nite
anonymous
  • anonymous
hey arman
anonymous
  • anonymous
I am becomeMyFan lol, got a new account because I got tired of my old name
anonymous
  • anonymous
hey loki=D
anonymous
  • anonymous
hello
anonymous
  • anonymous
how are you doin?
anonymous
  • anonymous
do you like my new name LOL
anonymous
  • anonymous
ok. bit tired. should be doing my work but wasting time
anonymous
  • anonymous
Yeah, it's cool...did BMF die?
anonymous
  • anonymous
yeah
anonymous
  • anonymous
sad
anonymous
  • anonymous
RIP, BMF
anonymous
  • anonymous
LOL =D, or as sstarica says it, ^_^
anonymous
  • anonymous
Is oktalBlizzard meant to mean something?
anonymous
  • anonymous
i just fanned you
anonymous
  • anonymous
All that work you did collecting fans, gone!
anonymous
  • anonymous
well, it is just my internet user name/ nick name.Oktal means base 8, and blizzard is a natural disaster LOL, thanx I fanned you too, the 132nd fan
anonymous
  • anonymous
=D yeah
anonymous
  • anonymous
As in base 8 for numbers?
anonymous
  • anonymous
but now I am planning to help people more once I learn some more stuff and write my exams
anonymous
  • anonymous
yes, for numbering system, like binary, octal, hexadecimal...
anonymous
  • anonymous
Cool.../random
anonymous
  • anonymous
well, I wanted it to be a bit diferent then my usual nicks
anonymous
  • anonymous
Arman's gone to bed
anonymous
  • anonymous
:)
anonymous
  • anonymous
How's the studying?
anonymous
  • anonymous
great
anonymous
  • anonymous
wow, you're probably the first person i've even asked that question who's said that
anonymous
  • anonymous
:) but really it is great, because I made up my mind to enjoy maths and physics and stuff like this
anonymous
  • anonymous
it is all about the attitude, I think
anonymous
  • anonymous
lol
anonymous
  • anonymous
it is
anonymous
  • anonymous
research backs it
anonymous
  • anonymous
If you assume, when you get to something in maths that you don't understand, that you can understand it eventually, well, the research says those people are more successful.
anonymous
  • anonymous
Took longer to say that than I had anticipated.
anonymous
  • anonymous
Remains of the day.
anonymous
  • anonymous
I just looked at my About me, and noticed something LOL, "...I have infinite interesting ideas but my limit is time..." coincidense but that actually reminds me of something I have learned in maths
anonymous
  • anonymous
lol
anonymous
  • anonymous
Should you be studying versus helping others?
anonymous
  • anonymous
well, I am actually solving questions my self, but once every hour or something I come here to solve a problem or two, to change the mental environment.
anonymous
  • anonymous
lol, okay. you seem sorted.
anonymous
  • anonymous
\[\sum_{\lim_{n \rightarrow \infty}}^{n} n\] where n is ideas something like this? can you improve it?
anonymous
  • anonymous
You could just say\[\left| \left\{ I_{oB} \right\} \right|=\infty\]
anonymous
  • anonymous
The cardinality (size) of the set of oktalBlizzard's ideas is infinite.
anonymous
  • anonymous
:) nice
anonymous
  • anonymous
too bad we can include maths symbols in about me text
anonymous
  • anonymous
You can refer people here to get a better idea.
anonymous
  • anonymous
=D
anonymous
  • anonymous
so, have you checked out the new study groups? Physics, Chemistry and Computer Science?
anonymous
  • anonymous
I had a look at physics yesterday and I was the only one online
anonymous
  • anonymous
me too
anonymous
  • anonymous
I haven't looked at the others.
anonymous
  • anonymous
I don't know anything else about the other subjects. Well, enough to offer any advice.
anonymous
  • anonymous
Q: How does one insult a mathematician? A: You say: "Your brain is smaller than any ε > 0"
anonymous
  • anonymous
lol, that's pretty good.
anonymous
  • anonymous
Theorem: Every positive integer is interesting. Proof: By contradiction, assume that there exists an uninteresting positive integer. Then there must be a smallest uninteresting positive integer. But that's pretty interesting! Therefore a contradiction!
anonymous
  • anonymous
Let epsilon be less than zero...
anonymous
  • anonymous
Are you coming up with this random stuff?
anonymous
  • anonymous
In some alley, a function meets up with a differential operator: "Get out of my way - or I'll differentiate you till you're zero!" "Try it - I'm \[e ^{x} \]..." "Too bad... I'm d/dy." no, I got this from a friend
anonymous
  • anonymous
I have one.
anonymous
  • anonymous
Pi had an argument with i. i told pi to be rational and pi told i to get real
anonymous
  • anonymous
Nice! LOL, I think I heared something like that, Check this: Salary Theorem: The less you know, the more you make. Proof: Fact #1: Knowledge is Power Fact #2: Time is Money We know that: Power = Work / Time And since Knowledge = Power and Time = Money It is therefore true that Knowledge = Work / Money Solving for Money, we get: Money = Work / Knowledge Thus, as Knowledge approaches zero, Money approaches infinity, regardless of the amount of Work done
anonymous
  • anonymous
Yeah, I think that's more sadly true than funny ;p
anonymous
  • anonymous
aiight OB, I have to go. Have to do some work before the days runs out and I feel guilty ;)
anonymous
  • anonymous
he also gave me this, but I dont get it at all, maybe you do: A SLICE OF PI ****************** 3.14159265358979 1640628620899 23172535940 881097566 5432664 09171 036 5 ok, bye, see you next time
anonymous
  • anonymous
hehe..see you :)
anonymous
  • anonymous
lolol

Looking for something else?

Not the answer you are looking for? Search for more explanations.