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Mathe III Lecture 8. Constrained Maximization. Lagrange Multipliers. At a maximum point of the original problem. the derivatives of the Lagrangian vanish (w.r.t. all variables). Constrained Maximization. Lagrange Multipliers. Intuition. y. iso- f curves. f(x,y) = K. 5. 20. 6.
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Mathe III Lecture 8
Constrained Maximization Lagrange Multipliers At a maximum point of the original problem the derivatives of the Lagrangian vanish (w.r.t. all variables).
Constrained Maximization Lagrange Multipliers Intuition y iso- f curves f(x,y) = K 5 20 6 assume + 5 20 x
Constrained Maximization Lagrange Multipliers Intuition y x
Constrained Maximization Lagrange Multipliers Intuition y x
Constrained Maximization Lagrange Multipliers Intuition y x
Constrained Maximization Lagrange Multipliers Intuition y x
Constrained Maximization Lagrange Multipliers Intuition A stationary point of the Lagrangian
Constrained Maximization Lagrange Multipliers Intuition A stationary point of the Lagrangian
Constrained Maximization The general case
The general case Constrained Maximization differentiating w.r.t. xs , s = m+1,…,n
The general case Constrained Maximization
The general case Constrained Maximization
The general case Constrained Maximization
The general case Constrained Maximization The derivatives w.r.t. xm+1,…..xnare zero at a max (min) point.
The general case Constrained Maximization
The general case Constrained Maximization But:
The general case Constrained Maximization
The general case Constrained Maximization We need to show this for s = 1,….m
The general case Constrained Maximization
The general case Constrained Maximization
The general case Constrained Maximization We have shown that a solution of the original problem satisfies
The general case Constrained Maximization i.e. a solution of the original problem is a stationary point of the Lagrangian :
Constrained Maximization Interpretation of the multipliers
Constrained Maximization Interpretation of the multipliers But:
Constrained Maximization Interpretation of the multipliers ??
Constrained Maximization Interpretation of the multipliers differentiate w.r.t. ci
Constrained Maximization Interpretation of the multipliers