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Block Systems


Let us consider the system in the form
 equation4436
where tex2html_wrap_inline9469, tex2html_wrap_inline9471 tex2html_wrap_inline9473 and tex2html_wrap_inline8581, tex2html_wrap_inline9477 If we represent the matrix A in the form
displaymath9405
then
displaymath9406
Let us find step by step the blocks tex2html_wrap_inline9479 and Ui:
displaymath9407

displaymath9408

displaymath9409

displaymath9410
To solve system (13), one must first solve the system
displaymath9411
We find that
displaymath9412

displaymath9413

displaymath9414
Secondly, we have to solve the system

displaymath9415

Example 6.6.1.* Let us solve the system of equations tex2html_wrap_inline6841 where
displaymath9416
This is a block system given by relation (13) since
displaymath9417
where tex2html_wrap_inline9487 and
displaymath9418

displaymath9419
We will express the matrix A in the form
displaymath9420

displaymath9421
Now we find
displaymath9422

displaymath9423

displaymath9424

displaymath9425

displaymath9426
and
displaymath9427
To find a solution of the system tex2html_wrap_inline6827, we shall solve two systems tex2html_wrap_inline6845 and tex2html_wrap_inline6847 The system tex2html_wrap_inline6845 can be expressed in the form
displaymath9428
where
displaymath9429

displaymath9430
and
displaymath9431

displaymath9432
Solving the system tex2html_wrap_inline9497 which can be given in the form
displaymath9433
we obtain
displaymath9434

displaymath9435
Thus,

displaymath9436