How to Find the Functional Extremum for Given Boundary Conditions?

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To find the functional extremum for the given boundary conditions, the functional S[x(t)] must be minimized or maximized using the Euler-Lagrange equations. The Lagrangian is defined as L = (dx/dt)² + x², and applying the Euler-Lagrange equations will yield a differential equation that the solution must satisfy. There is no need to express the Lagrangian differently, as the existing form is suitable for integration. The integral is used to evaluate the functional, but the primary method for finding extrema is through the differential equation derived from the Euler-Lagrange approach. This process ensures that the curve meets the specified boundary conditions while optimizing the functional.
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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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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.
 

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