MATH307 April 2006
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Question 05 (d)
A matrix A and a vector b are given by
Determine if is solvable. Find x if it is solvable and find x (i.e. the least squares solution) if it is not.
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From part c, we note b is not in R(A) therefore it is not solvable.
We will proceed by solving the least squares solution by QR decomposition
A=QR from part a
since Q has columns of orthonormal vectors, Q is orthogonal
The solution to our least square problem is