Solve Separable DiffEQ: Find General Solution & Functions | Help Needed!

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Homework Help Overview

The discussion revolves around a separable differential equation, where participants are attempting to find the implicit general solution of the form F(x,y) = G(x) + H(y) = K. The original poster expresses frustration over incorrect submissions related to this problem.

Discussion Character

  • Exploratory, Mathematical reasoning, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the integration of both sides of the equation and suggest inserting parentheses to clarify the expression. There are also references to specific integrals related to the equation, and participants share their own attempts at finding the solution.

Discussion Status

Some participants have offered guidance on how to structure the solution, including the order of functions and the need to manipulate terms. There is an ongoing exploration of different approaches to arrive at the correct form of the solution, with no clear consensus yet.

Contextual Notes

Participants are working under the constraints of homework rules, which may limit the information they can share or the methods they can use. There is also a sense of frustration regarding the feedback received on their submissions.

mr_coffee
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Can't figure out this seperable diffEQ! :(

Hello everyone 'ive been trying to figure out this easy looking Differential Equation and yet its wrong! weee!
Here is the problem:
http://cwcsrv11.cwc.psu.edu/webwork2_files/tmp/equations/58/6217226076d5fd259f53ad1e3ed4071.png
has an implicit general solution of the form F(x,y) = K.
In fact, because the differential equation is separable, we can define the solution curve implicitly by a function in the form
F(x,y) = G(x) + H(y) =K.

Find such a solution and then give the related functions requested.
F(x,y) = G(x) + H(y) = ?

I submitted:
http://cwcsrv11.cwc.psu.edu/webwork2_files/tmp/equations/5a/1bcf742ffddc932f739864bc6d3e4a1.png
which was wrong.


here is my work:
http://img202.imageshack.us/img202/9317/lastscan6uc.jpg

Any help would be fantastical. <--yeah I'm pretty sure that's not a word.:bugeye:
 
Last edited by a moderator:
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Go back and insert a pair of parens on the left hand side of the second line that it would read

[tex]\int e^y(\sin y+9\cos y) dy = \int(14x+5)dx[/tex]
 
Know also that

[tex]\int e^y(\sin y+9\cos y) dy = e^y(5\sin y+4\cos y)[/tex]

and in closing note that fantastical is now a word by extension, since, for example antideparameterizationism is likwise wise a word, for I am very much opposed to not eliminating a perfectly useful paramter from my solutions (especially once they've been obtained by inserting it cleverly into the givens,) and I am thus a practioner of antideparameterizationalism. :smile:
 
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hah i like your way of thinking.
I submitted
http://cwcsrv11.cwc.psu.edu/webwork2_files/tmp/equations/08/74e463c2a0d2a1740eacdf142dadd41.png
and they told me to f off, i was quite distraught. Any ideas what i did now
?
 
Last edited by a moderator:
try writing it in the order (fcn. of x) + (fcn. of y), e.g. G(x) + H(y), such as

-7*x^2-5*x + 5*exp(y)*sin(y)+4*exp(y)*cos(y)
 
ur the man!
For some reason, i had to multiply through -1 to make it work, it loved this answer:http://cwcsrv11.cwc.psu.edu/webwork2_files/tmp/equations/e6/513e4938c92e397902bfbf80c0e9551.png
 
Last edited by a moderator:

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