Homework Statement
Prove carefully that the following map has a horseshoe for one positive value of \mu
xn+1 = xn2 - \mu
For what positive values of \mu will the map have a horseshoe?
Homework Equations
The Attempt at a Solution
xn+1 = xn2 - \mu = g(xn,\mu)
∂g/∂x = 2x
→ turning pt...
Homework Statement
If β=0 the neurone model is \dot{u}= -u
\dot{v}= v2 + v - u + \delta
If \delta = 1/4 it has critical point (0,-1/2)
Transform the system so that the critical point is at the origin so let \bar{v} = v +1/2 and find the equations of motion for (u,\bar{v})
Homework...
Suppose \alpha(x0) enters and does not leave some closed and bounded domain D that contains no critical points. This means that \phi(x0, t) \in D for all t≥\tau, for some \tau≥0. Then there is at least one periodic orbit in D and this orbit is in the \omega-limit set of x0.
What does this...
So the flow enters the trapping region about the origin which has no critical points which means it is a stable periodic orbit in the trapping region..
There can't be any fixed points in trapping region. There can be a fixed point at the origin? So to determing the stability I determine the fixed point at the origin?
So if I have to give bounds for the periodic orbit I can pick any value for r(small) provided r'>0 and then choose another value (this time larger) and show r'<0? How would I then determine its stability characteristics?
Okay so does this mean
1≤g(θ)≤3 So you get
\dot{r} = 2r - r3g(θ)
\dot{r} > 2r - 3r3 > 0 and so 2/3 > r2
\dot{r} < 2r - r3 < 0 and so r2 > 2
and √(2/3) < r < √2
Homework Statement
System in polar coordinates
\dot{r} = 2r - r3(2 + sin(\theta)),
\dot{\theta} = 3 - r2
Use a trapping region to show there is at least one periodic orbit?
Homework Equations
By using Poincare Bendixson's Theorem
The Attempt at a Solution
I am struggling to...
Homework Statement
z→x3+ i(1 - y)3: Show where the functions is analytic and differentiable.
Homework Equations
The Attempt at a Solution
For a function to be analytic cauchy-riemann equations must hold.. so
ux = vy and uy = -vx
Now f(z) = x3 + i(1 - y)3 is already in the...
Homework Statement
Identify the stable, unstable and center eigenspaces for
\dot{y} = the 3x3 matrix
row 1: 0, -3, 0
row 2: 3, 0, 0
row 3: 0, 0, 1
Homework Equations
The Attempt at a Solution
This is an example used from the lecture and I understand how to get the...
I have come up with this
Taking the limit along the Real axis:
lim as z→0 of (z/\bar{z})2
= lim (x + 0i)2/(x - 0i)2
= lim x2/x2
= 1
Then taking the limit at the points x + xi for x→0:
lim as z→0 of (z/\bar{z})2
= lim (x + xi)2/(x - xi)2
= lim (2x2)/(-2x2)
= -1
and since 1 ≠ -1...
Homework Statement
Show that the lim z→0 of (z/\bar{z})2 does not exist
Homework Equations
The Attempt at a Solution
Not to sure how to go about this question?
Homework Statement
Find all complex solutions to \bar{z} = z
Homework Equations
z = x + iy and \bar{z} = x - iy
The Attempt at a Solution
What does it mean by find all complex solutions?
\bar{z} = z
0 = x + iy - x + iy
0 = 2iy