How to Find the Functional Extremum for Given Boundary Conditions?

In summary, the conversation is about finding a curve that satisfies certain criteria in order to make a given functional an extremum. The functional is defined as the integral of a function involving the derivative and the square of the function itself. The discussion also involves the use of the Euler-Lagrange equations to find a differential equation that the solution must satisfy.
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Homework Statement


I have been given a functional
$$S[x(t)]= \int_0^T \Big[ \Big(\frac {dx(t)}{dt}\Big)^{2} + x^{2}(t)\Big] dt$$
I need a curve satisfying x(o)=0 and x(T)=1,
which makes S[x(t)] an extremum

Homework Equations



Now I know about action being
$$S[x(t)]= \int_t^{t'} L(\dot x, x) dt$$
and in this equation $$ L= \Big(\frac {dx(t)}{dt}\Big)^{2} + x^{2}(t)$$

The Attempt at a Solution


Is there any other way I can express Lagrangian to fit in this equation and hence I can do the integral? and is there any general solution for the lagrangian?
 
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  • #2
Why do you want to do the integral? What is wrong with using the Euler-Lagrange equations? This will give you a differential equation that your solution must satisfy to be an extremum the functional.
 

FAQ: How to Find the Functional Extremum for Given Boundary Conditions?

What is the purpose of finding the functional extremum?

The purpose of finding the functional extremum is to determine the maximum or minimum value of a function. This can be useful in various fields such as engineering, economics, and physics, as it allows for optimization and prediction of outcomes.

How is the functional extremum calculated?

The functional extremum is calculated using methods such as differentiation, optimization algorithms, and numerical methods. These techniques involve finding critical points and determining whether they are maximum or minimum values.

What are some common applications of finding the functional extremum?

Finding the functional extremum has many applications, including determining the most efficient route for transportation, maximizing profits in business, and optimizing the design of structures or systems.

What are the limitations of finding the functional extremum?

One limitation of finding the functional extremum is that it assumes the function is continuous and differentiable. In real-world scenarios, this may not always be the case. Additionally, the extremum value may not always be a practical solution.

Can finding the functional extremum be applied to multi-variable functions?

Yes, finding the functional extremum can be applied to functions with multiple variables. This involves finding the critical points and determining whether they are maximum or minimum values in each variable.

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