Envelope Theorem - General Envelope Theorem

There also exists a version of the theorem, called the general envelope theorem, used in constrained optimization problems which relates the partial derivatives of the optimal-value function to the partial derivatives of the Lagrangian function.

We are considering the following optimization problem in formulating the theorem (max may be replaced by min, and all results still hold):

Which gives the Lagrangian function:

Where:

is the dot product

Then the general envelope theorem is:

Note that the Lagrange multipliers are treated as constants during differentiation of the Lagrangian function, then their values as functions of the parameters are substituted in afterwards.

Read more about this topic:  Envelope Theorem

Famous quotes containing the words general, envelope and/or theorem:

    Towards him they bend
    With awful reverence prone; and as a God
    Extoll him equal to the highest in Heav’n:
    Nor fail’d they to express how much they prais’d,
    That for the general safety he despis’d
    His own: for neither do the Spirits damn’d
    Loose all thir vertue; lest bad men should boast
    Thir specious deeds on earth, which glory excites,
    Or close ambition varnisht o’er with zeal.
    John Milton (1608–1674)

    Life is not a series of gig lamps symmetrically arranged; life is a luminous halo, a semi-transparent envelope surrounding us from the beginning of consciousness to the end.
    Virginia Woolf (1882–1941)

    To insure the adoration of a theorem for any length of time, faith is not enough, a police force is needed as well.
    Albert Camus (1913–1960)