Trouble with particular solution of differential equation - rewrite my answer?

cowmoo32
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Trouble with particular solution of differential equation - [SOLVED]

Homework Statement


Find the particular solution of the differential equation
c995a54ca48d21f6dc81446bdd54881.png

satisfying the initial condition
907c69d9098d2e376491d1dfd7f0771.png



The Attempt at a Solution


[STRIKE]I end up with (1/2)ln(-x^2+10x) which does satisfy the initial conditions, yet it's coming back as incorrect. Is there another way I can write the formula?[/STRIKE]

I figured it out, check post #3
 
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cowmoo32 said:

Homework Statement


Find the particular solution of the differential equation
c995a54ca48d21f6dc81446bdd54881.png

satisfying the initial condition
907c69d9098d2e376491d1dfd7f0771.png



The Attempt at a Solution


I end up with (1/2)ln(-x^2+10x) which does satisfy the initial conditions, yet it's coming back as incorrect. Is there another way I can write the formula?
Show how you got the result you show. I assume you mean y = (1/2)ln(-x2 + 10x).

Satisfying the initial conditions is not enough: the solution has to satisfy the differential equation, too.
 
Scratch that above, I had a negative out of place. See below. I corrected it and it's coming back as correct.

\frac{dy}{dx}=e-2x(x-5)

\int (e2y)dy = \int (x-5)dx

e2y = x2 - 10x + C

2y = ln(x2 - 10x + C)

C = 50
 
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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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