Differential equation with only the trivial solution

In summary, the conversation explored the idea of finding a differential equation with its only complex-valued solution being y=0. The participants discussed various attempts and concluded that a function of y' that cannot be zero, such as f(y')=1 or f(y')=1+(y')(y'*), can be used to create a non-trivial equation with the desired solution. The use of Wronskian matrices was also mentioned, but it was ultimately determined that there are no non-trivial equations that reduce to y=0.
  • #1
Bipolarity
776
2

Homework Statement


Find a differential equation with its only (complex-valued) solution being y=0

Homework Equations


The Attempt at a Solution


I believe that there is no DE having only y=0 as its solution, but frankly I am not sure if this is the case. I would like to know whether or not this is true, so that I know in which direction I can begin working my proof (or at least a hint is appreciated).

Also, something (in my mind) tells me this problem may have some connection with Wronskian matrices, but I have no clue really.

EDIT: I tried playing with some random diff Eqs, it seems that there are in fact trivial things like y+y'-y'=0, but this type of answer seems to be trivial to be of substance. Is there a DE that does not reduce to a trivial y=0?

Thanks!

BiP
 
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  • #2
One approach is to think of a function of y' that cannot be zero, f(y') say, then write f(y')y = 0.
 
  • #3
haruspex said:
One approach is to think of a function of y' that cannot be zero, f(y') say, then write f(y')y = 0.

Well, f(y')=1 works. Still seems like kind of a cheat. Notice they also said complex valued. So something like f(y')=1+(y')^2 won't work either. Not to say you can't cook one up. Like f(y')=(1+(y')(y'*)). I'm just wondering if there is something nontrivial here.
 
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  • #4
I was thinking of ey'y=0
 
  • #5
haruspex said:
I was thinking of ey'y=0

Good work! And thanks!

BiP
 

FAQ: Differential equation with only the trivial solution

What is a differential equation with only the trivial solution?

A differential equation with only the trivial solution is an equation where the only solution is when the dependent variable is equal to a constant. This means that the equation has no varying values and is essentially a straight line.

What causes a differential equation to have only the trivial solution?

Differential equations with only the trivial solution occur when the equation is homogeneous and linear, and the coefficients of the equation are all equal to zero. This results in a solution where the dependent variable is equal to a constant, as there are no varying terms to solve for.

What is the significance of a differential equation with only the trivial solution?

A differential equation with only the trivial solution may not have a practical application, as it does not represent a changing or dynamic system. It is often used as a benchmark to compare against more complex solutions and to determine if a solution is non-trivial.

Can a differential equation with only the trivial solution have multiple solutions?

No, a differential equation with only the trivial solution can only have one solution, which is when the dependent variable is equal to a constant. This is because there are no varying terms in the equation to produce multiple solutions.

How is a differential equation with only the trivial solution solved?

A differential equation with only the trivial solution is already in its simplest form and does not require solving. The solution is simply when the dependent variable is equal to a constant, and this can be verified by substituting the constant into the original equation.

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