How Do I Solve y''+4y'+4y=2+3e^2x and Find Related Resources?

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unfortunatly i have lost a question paper which has questions like y''+y'+y=sinx or =e^2x or =X+2-4+e^2x or=2^-3x+5E^-5e etc etc, i have the questions and answers for the y''+y'+y=0 format questions but none of the non zero questions so my question is 2 fold

first of all how do i go about answering y''+4y'+4y=2+3e2x

and second of all has anyone got leeds university MATH1400 sheet 4 questions for this year and if not which is the responce I'm expecting has anyone got any ideas where i can find examples of questions like this? thanks
 
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You want to set up the "characteristic equation" for
y'' + 4y' + 4y = 0 first and solve this for the values of r which will give you the solutions y = e^(rx) for the homogeneous equation.

You will find that this has a repeated root. How do you handle that?

The next step will be to use something like the method of undetermined coefficients to find the "particular solution" for the non-homogenous equation you started with.
 
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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