|  | @@ -166,10 +166,10 @@ Before going further, let us make some notational simplifications. We
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				|  |  |  will assume that the matrix :math:`\frac{1}{\sqrt{\mu}} D` has been concatenated
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				|  |  |  at the bottom of the matrix :math:`J` and similarly a vector of zeros
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				|  |  |  has been added to the bottom of the vector :math:`f` and the rest of
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				|  |  | -our discussion will be in terms of :math:`J` and :math:`f`, i.e, the
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				|  |  | +our discussion will be in terms of :math:`J` and :math:`F`, i.e, the
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				|  |  |  linear least squares problem.
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				|  |  |  
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				|  |  | -.. math:: \min_{\Delta x} \frac{1}{2} \|J(x)\Delta x + f(x)\|^2 .
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				|  |  | +.. math:: \min_{\Delta x} \frac{1}{2} \|J(x)\Delta x + F(x)\|^2 .
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				|  |  |     :label: simple
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				|  |  |  
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				|  |  |  For all but the smallest problems the solution of :eq:`simple` in
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				|  | @@ -648,11 +648,11 @@ can be quite substantial.
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				|  |  |       access to :math:`S` via its product with a vector, one way to
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				|  |  |       evaluate :math:`Sx` is to observe that
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				|  |  |  
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				|  |  | -     .. math::  x_1 &= E^\top x
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				|  |  | -     .. math::  x_2 &= C^{-1} x_1
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				|  |  | -     .. math::  x_3 &= Ex_2\\
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				|  |  | -     .. math::  x_4 &= Bx\\
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				|  |  | -     .. math::   Sx &= x_4 - x_3
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				|  |  | +     .. math::  x_1 &= E^\top x\\
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				|  |  | +                x_2 &= C^{-1} x_1\\
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				|  |  | +                x_3 &= Ex_2\\
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				|  |  | +                x_4 &= Bx\\
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				|  |  | +                Sx &= x_4 - x_3
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				|  |  |          :label: schurtrick1
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				|  |  |  
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				|  |  |       Thus, we can run PCG on :math:`S` with the same computational
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