Find Steady States for Equations: u, v and Get Help with Steady State Question

In summary, the conversation discusses finding steady state solutions for two equations and their corresponding working. The first equation has three steady state solutions, while the second equation has one additional solution. There is some confusion about the working for the fourth solution, but it is mentioned that there may be help needed for that part.
  • #1
mt91
15
0
Got a steady state question and was wondering if anyone would be able to check if I'm on the right track?

Find the steady states of these two equations:

1596287107517.png


My working out as far:

\[ 0=u*(1-u*)(a+u*)-u*v* \]
\[ 0=v*(bu*-c) \]

I looked at the 2nd equation first giving:
\[ v*=0, u*=c/b \]

subbing v*=0 into equation 1 gave:
\[ 0=u*(1-u*)(a+u*) \]
\[ u*=0, u*=1, u*=-a \]
\[ v=a+c/b - ac/b-c^2/b^2 \]

Not sure about that part of the steady state question so any help would be really helpful, cheers

Giving three steady states of
(0,0), (1,0), (-a,0)

Then I looked at subbing u*=b/c. (However this part of my working got confusing and I'm not entirely sure if it was correct.

\[ 0=c/b(1-c/b)(a+c/b)-cv/b \]
\[ cv/b=c/b-c^2/b^2(a+c/b) \]
 
Physics news on Phys.org
  • #2
mt91 said:
Got a steady state question and was wondering if anyone would be able to check if I'm on the right track?

Find the steady states of these two equations:

View attachment 10548

My working out as far:

\[ 0=u*(1-u*)(a+u*)-u*v* \]
\[ 0=v*(bu*-c) \]

I looked at the 2nd equation first giving:
\[ v*=0, u*=c/b \]
Either v*= 0 or u*=c/b

subbing v*=0 into equation 1 gave:
\[ 0=u*(1-u*)(a+u*) \]
\[ u*=0, u*=1, u*=-a \]
Yes, (u*, v*)= (0, 0), (1, 0), and (-a, 0) are three steady state solutions.

\[ v=a+c/b - ac/b-c^2/b^2 \]
Yes, substituting u*= c/b into 0=u*(1-u*)(a+u*)-u*v* gives 0= (c/b)(1- c/b)(a+ c/b)- (c/b)v* .
(c/b)v*= (c/b)(1- c/b)(a+ c/b) so v*= (1- c/b)(a+ c/b)= a- ac/b+ c/b- c^2/b^2

So a fourth steady state solution is (u*, v*)= (c/b, a+ c/b- ac/b- c^2/b^2).

Not sure about that part of the steady state question so any help would be really helpful, cheers

Giving three steady states of
(0,0), (1,0), (-a,0)

Then I looked at subbing u*=b/c. (However this part of my working got confusing and I'm not entirely sure if it was correct.

\[ 0=c/b(1-c/b)(a+c/b)-cv/b \]
\[ cv/b=c/b-c^2/b^2(a+c/b) \]
 

1. What is a steady state?

A steady state is an equilibrium point in a system where the values of all variables remain constant over time. In other words, the system is not changing over time and is in a state of balance.

2. How do I find steady states for equations?

To find steady states for equations, you need to set the derivatives of all variables to zero and solve for the values of the variables. These values will be the steady states for the system.

3. Can steady states change over time?

No, steady states do not change over time. They are constant values that represent a balance in the system. However, the system itself may change over time and reach a new steady state.

4. What is the importance of finding steady states for equations?

Finding steady states for equations allows us to understand the behavior of a system and predict its future state. It also helps us identify critical points and analyze the stability of the system.

5. How can I get help with a steady state question?

If you need help with a steady state question, you can consult with a math or science tutor, reach out to your professor or classmates, or use online resources such as forums or study groups. It is important to fully understand the concept of steady states before attempting to solve any equations related to it.

Similar threads

  • Classical Physics
Replies
9
Views
956
Replies
2
Views
943
  • Engineering and Comp Sci Homework Help
Replies
6
Views
1K
  • Introductory Physics Homework Help
Replies
7
Views
1K
  • Classical Physics
Replies
8
Views
6K
  • Differential Equations
Replies
1
Views
1K
  • Advanced Physics Homework Help
Replies
14
Views
1K
  • Engineering and Comp Sci Homework Help
Replies
3
Views
1K
Replies
19
Views
3K
  • Calculus and Beyond Homework Help
Replies
9
Views
593
Back
Top