- #1
gkirkland
- 11
- 0
My DE skills are a bit rusty, and I need some help remembering how to handle a system such as:
[itex]\dot{x_1}=x_2[/itex]
[itex]\dot{x_2}=-2x_1-3x_2+sint+e^t[/itex]
I have found the homogeneous solution to be (sorry I don't know how to do matrices here):
[itex]c_1\left\{e^{-t}\right\}+c_2\left\{e^{-2t}\right\}[/itex]
[itex]c_1\left\{-e^{-t}\right\}+c_2\left\{-2e^{-2t}\right\}[/itex]
From what I've found online I should guess a particular solution form:
[itex]x_{p}=Asin(t)+Bcos(t)+Ce^{t}[/itex]
Where A, B, and C are 2x1 matrices of constants [itex]a_1, a_2, b_1, b_2, c_1, c_2[/itex]
Is this correct?
Then rewrite the original in the form:
[itex]\dot{x_{p}}=Ax_{p}+g[/itex]
Then differentiate the guess and substitute back into the above.
Assuming this is all correct, what are the next steps in finding the general solution?
[itex]\dot{x_1}=x_2[/itex]
[itex]\dot{x_2}=-2x_1-3x_2+sint+e^t[/itex]
I have found the homogeneous solution to be (sorry I don't know how to do matrices here):
[itex]c_1\left\{e^{-t}\right\}+c_2\left\{e^{-2t}\right\}[/itex]
[itex]c_1\left\{-e^{-t}\right\}+c_2\left\{-2e^{-2t}\right\}[/itex]
From what I've found online I should guess a particular solution form:
[itex]x_{p}=Asin(t)+Bcos(t)+Ce^{t}[/itex]
Where A, B, and C are 2x1 matrices of constants [itex]a_1, a_2, b_1, b_2, c_1, c_2[/itex]
Is this correct?
Then rewrite the original in the form:
[itex]\dot{x_{p}}=Ax_{p}+g[/itex]
Then differentiate the guess and substitute back into the above.
Assuming this is all correct, what are the next steps in finding the general solution?