- #1

rularn

- 8

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Hi!

I have this x'[t] + x[t] = a + Sin[b*t] diff.equ that I would like to solve with matlab/simulink.

Let set a=1, b=1 and

x(0)=2

I know that x(t) = 1/2 e^-t (-cos(t) e^t+sin(t) e^t+2 e^t+3) and what it look like (see pic). I aslo got the transfer equ G(s) from Laplace and it should be:

G(s) = (a/s+b/(b^2+s^2))/(s+1),

The only thing I don't get right is the initial value as you can see at the pic. It also shows what it should look like. What do I do wrong?

It should be easier to use the transfer equ G(s), but I don't get that right either. Any suggestions?

http://img205.imageshack.us/img205/821/reglerth3.jpg

Thank you!

## Homework Statement

I have this x'[t] + x[t] = a + Sin[b*t] diff.equ that I would like to solve with matlab/simulink.

Let set a=1, b=1 and

x(0)=2

## Homework Equations

I know that x(t) = 1/2 e^-t (-cos(t) e^t+sin(t) e^t+2 e^t+3) and what it look like (see pic). I aslo got the transfer equ G(s) from Laplace and it should be:

G(s) = (a/s+b/(b^2+s^2))/(s+1),

## The Attempt at a Solution

The only thing I don't get right is the initial value as you can see at the pic. It also shows what it should look like. What do I do wrong?

It should be easier to use the transfer equ G(s), but I don't get that right either. Any suggestions?

http://img205.imageshack.us/img205/821/reglerth3.jpg

Thank you!

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