Undergrad Calculus of Variations Dependent variables and constraints

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In the context of minimizing the function f(x,x',y,y',t) under the constraint g(x,x',y,y',t), the discussion focuses on the application of Euler-Lagrange equations for the dependent variables x and y. It is debated whether to use a single constant A in the modified function f(x,x',y,y',t) - Ag(x,x',y,y',t) for both equations or if each equation should have a distinct constant. The need for explicit equations defining the constraint is emphasized, as this will clarify the set of generalized coordinates. The proper formulation of these equations is crucial for accurately applying the calculus of variations. Understanding these elements is essential for effectively addressing the problem at hand.
shedrick94
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If we have a function:

\begin{equation} f(x,x',y,y',t) \end{equation} and we are trying to minimise this subject to a constraint of
\begin{equation} g(x,x',y,y',t) \end{equation}

Would we simply have a set of two euler lagrange equations for each dependent variable, here we have x and y.

Would we insert f(x,x',y,y',t)-Ag(x,x',y,y',t) into both equations, where A is a constant? Or would each equation require a different constant in front of the constraint term g(x,x',y,y',t)??
 
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shedrick94 said:
and we are trying to minimise this subject to a constraint of.
g(x,x′,y,y′,t)​
(2)(2)g(x,x′,y,y′,t)\begin{equation} g(x,x',y,y',t) \end{equation}

Would we simply have a set of two euler lagrange equations for each dependent variable, here we have x and y.

pl. give explicit eq of constraint -that will define the set of generalized coordinates.
 
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