# Math Help - steady state solution of a differential equation

1. ## steady state solution of a differential equation

Hey.

I am taking a matlab class and my instructor is absolutely horrendous. he does not teach us anything, but asks questions on everything.

I'm having a problem with the following question:

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What is a steady state solution of a differential equation? How can i solve the attached problem in matlab?

Thanks a lot.

2. ## Re: steady state solution of a differential equation

Originally Posted by asi123
Hey.

I am taking a matlab class and my instructor is absolutely horrendous. he does not teach us anything, but asks questions on everything.

I'm having a problem with the following question:

ImageShack&#174; - Online Photo and Video Hosting

What is a steady state solution of a differential equation?...
The 'steady state solution' of this DE is of the type...

$y(t)= a\ \cos (b\ t + c)$ (1)

... where a, b and c are independent from t. The constants a, b and c can be found computing...

$y^{'}(t)= - a\ b\ \sin (b\ t + c)$ (2)

$y^{''}(t)= - a\ b^{2}\ \cos (b\ t + c)$ (3)

... inserting (2) and (3) in the DE...

$3\ y^{''} +4\ y^{'} - 5\ y = 4\ \cos 2t$ (4)

... and imposing equality...

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