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Arnold's Trivium
1991 Arnold's Trivium
26
26
Part of
1991 Arnold's Trivium
Problems
(1)
Problem 26
Source:
7/1/2010
Investigate the behaviour as
t
→
+
∞
t\to+\infty
t
→
+
∞
of solutions of the systems
{
x
˙
=
y
y
˙
=
2
sin
y
−
y
−
x
\begin{cases} \dot{x}=y\\ \dot{y}=2\sin y-y-x\end{cases}
{
x
˙
=
y
y
˙
=
2
sin
y
−
y
−
x
{
x
˙
=
y
y
˙
=
2
x
−
x
3
−
x
2
−
ϵ
y
\begin{cases} \dot{x}=y\\ \dot{y}=2x-x^{3}-x^{2}-\epsilon y\end{cases}
{
x
˙
=
y
y
˙
=
2
x
−
x
3
−
x
2
−
ϵy
where
ϵ
≪
1
\epsilon\ll 1
ϵ
≪
1
.
trigonometry