- #1
bobred
- 173
- 0
Homework Statement
In the limit as t→∞, the solution approaches [tex]x(t) =K \sin[ω(t − t_0)][/tex]
where K and t0 depend on ω. A>0 and ω≥0. Show that
[tex]K(ω) = \frac{A}{\sqrt{ω^4 + 2ω^2 + 1}}[/tex]
.
Homework Equations
Here is the differential equation
[tex]\frac{\textrm{d}^{2}x}{\textrm{d}t^{2}}+2\frac{\textrm{d}x}{\textrm{d}t}+x=A\sin(\omega t)[/tex]
The Attempt at a Solution
Here is the general solution
[tex]x=\left(C+Dt\right)e^{-t}-\frac{A\left(2\omega\cos\left(\omega t\right)+\omega^{2}\sin\left(\omega t\right)-\sin\left(\omega t\right)\right)}{\omega^{4}+2\omega^{2}+1}[/tex]
As t get large the exponential term vanishes but cannot see how the solution approaches [tex]x(t) =K \sin[ω(t − t_0)][/tex]
Any pointers?