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March 20th, 2017, 10:01 AM   #1
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Unhappy Please enlighten me.

Hello Redeemer,

I got stuck at $\displaystyle (d^4y/dx^4)+3(d^2y/dx^2)^5+5y=0$.

I'm not sure what method I should do.

Thanks a lot for your help.
TheNewDiff
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March 20th, 2017, 03:48 PM   #2
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Try$\displaystyle \;$ $\displaystyle y=e^{kx}$
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March 20th, 2017, 04:09 PM   #3
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Originally Posted by TheNewDiff View Post
Hello Redeemer,

I got stuck at $\displaystyle (d^4y/dx^4)+3(d^2y/dx^2)^5+5y=0$.

I'm not sure what method I should do.

Thanks a lot for your help.
TheNewDiff
The best I've come up with is y(x) = 0. You'll probably find that the solution(s) can only be found by numerical methods.

-Dan
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March 20th, 2017, 10:17 PM   #4
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The best I've come up with is y(x) = 0. You'll probably find that the solution(s) can only be found by numerical methods.

-Dan
Hi Dan,
Could you please show me the step,please?
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March 21st, 2017, 02:14 AM   #5
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Hi Dan,
Could you please show me the step,please?
There was no method. I simply noted that y = 0 is a solution. It's one of the first things I look for, especially when dealing with a non-linear equation.

-Dan
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June 18th, 2017, 10:37 AM   #6
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Was this an initial value problem? If so, please post the initial conditions. Thanks!
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December 9th, 2017, 04:27 PM   #7
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Was this an initial value problem? If so, please post the initial conditions. Thanks!
Don't have any initial value problem when I browns the book.
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December 9th, 2017, 06:34 PM   #8
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The vector field for this is analytic so the formal power series solution will be the unique solution.
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