How can I effectively solve two challenging differential equations problems?

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The discussion revolves around solving two challenging differential equations problems. For problem 10, the user applied reduction of order, assuming one solution is y1=e^x, leading to y2=xe^x, and inquired about using variation of parameters for the particular solution. For problem 7, the user multiplied by x^p y^q to find partial derivatives and equated them to ensure the equation is exact, resulting in messy fractional values for p and q. Responses confirm that the approaches taken are correct, even if the results are complicated. Overall, both problems involve standard methods in differential equations, with validation from peers on the user's methods.
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Homework Statement


I have two problems from my differential equations assignment that I'm having difficulty with. I would appreciate some guidance!


Homework Equations



http://img10.imageshack.us/img10/3397/questionsk.th.jpg

The Attempt at a Solution


for no.10 I used reduction of order with the assumption that one solution is y1=e^x
I got y2=xe^x

my question is for this question do I solve the unhomogenous equation by variation of parameters to solve for the particular solution And from there use it for the General Solution ? ( yg= yh+yp.

For no.7
I multiplied by x^p y^q and found the partial derivatives My and Nx.
Inorder for it to be exact, I equated the partial derivatives and found my values for p and q. They came out to being fractions and my final solution is extremely messy with fractions. Is this is correct approach?

Thanks.
 
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FaradayLaws said:

Homework Statement


I have two problems from my differential equations assignment that I'm having difficulty with. I would appreciate some guidance!


Homework Equations



http://img10.imageshack.us/img10/3397/questionsk.th.jpg

The Attempt at a Solution


for no.10 I used reduction of order with the assumption that one solution is y1=e^x
I got y2=xe^x

my question is for this question do I solve the unhomogenous equation by variation of parameters to solve for the particular solution And from there use it for the General Solution ? ( yg= yh+yp.
Yes.

for no.7
I multiplied by x^p y^q and found the partial derivatives My and Nx.
Inorder for it to be exact, I equated the partial derivatives and found my values for p and q. They came out to being fractions and my final solution is extremely messy with fractions. Is this is correct approach?
Did you get 3q= 2(p+1) and 20(q-1)= 12(p+ 3)? That's what I got. Yes, those give "messy" fractions.

Thanks.[/QUOTE]
 
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I picked up this problem from the Schaum's series book titled "College Mathematics" by Ayres/Schmidt. It is a solved problem in the book. But what surprised me was that the solution to this problem was given in one line without any explanation. I could, therefore, not understand how the given one-line solution was reached. The one-line solution in the book says: The equation is ##x \cos{\omega} +y \sin{\omega} - 5 = 0##, ##\omega## being the parameter. From my side, the only thing I could...
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