Mathematics for Economists

(Greg DeLong) #1

Calculus of variations


2 π

ZT
0

x(t)

r
1 +




x

 2


dt!min
x( 0 )=a
The solution of the EulerñLagrange equation is still of the form

x(t)=αch





α




but we should also have the conditionx( 0 )=aand the transversality
0 = φ^0 b(x(b))=Fx^0




b,x(b),x(b)




=



rx(T)x(T)
1 +




x(T)

 2.


That isx(T)orx(T)is zero which is impossible for functionch(t)..
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