How to Find the Functional Extremum for Given Boundary Conditions?

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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?
 
Physics news on Phys.org
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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