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#1 Re: Help Me ! » Can somebody solve this matrix question » 2014-02-14 05:35:59
hi vanilla,
Welcome to the forum.
X - XV = U -X(U-V) = U - XU + XV
X - 2XV + XU = X(I - 2V + U) = U
X = U(I - 2V + U)-¹
So compute that bracket, find its inverse, and do U times that inverse, maintaining that order.
Hope that helps,
Bob
Thank you very much! 
#2 Re: Help Me ! » Can somebody solve this matrix question » 2014-02-14 03:40:53
Hi vanilla
If you want to check your solution, this is what I'm coming up with:
Thank you very much! It was an exercise from an exam. Indeed, I got the same result, but some colleagues with whom I spoke said that they have different determinants. Some got -3, others -6 or -7. They determined the same matrix X. That is why I was shocked because I got determinant -2 and recalculated the matrix several times since then. It is such a relief now! Thank you once again!!! 
#3 Help Me ! » Can somebody solve this matrix question » 2014-02-13 23:43:10
- vanilla
- Replies: 4
Given is the matrix equation
X-XV=U-X(U-V)
(a) Determine matrix X
(b) Compute X when
4 3 1
3 2 -1 ---> U
8 5 3
2 1 1
0 1 -2 ---> V
2 1 2
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