for Newton's equation, we have Lagrange function which can give the solution while its variation equates 0.
however, what about the situation for a general differential equation.
is this method can deal with such general situation? and how can we find out the corresponding "Lagrange function".
thanks for any reply and links.
however, what about the situation for a general differential equation.
is this method can deal with such general situation? and how can we find out the corresponding "Lagrange function".
thanks for any reply and links.