96.4k views
3 votes
Transcribed image text:

An orthogonal basis for A, ⎣


−10
2
−6
16
2

−4
8
−12
16
8

−1
5
−3
22
5

−1
10
−3
22
0




, is ⎩






−10
2
−6
16
2




, ⎣


3
3
−3
0
3




, ⎣


6
0
6
6
0




, ⎣


0
5
0
0
−5








. Find the QR factorization of A with the given orthogonal basis. The QR factorization of A is A=QR, where Q= and R=

1 Answer

7 votes

To find the QR factorization of matrix A using the given orthogonal basis, we can use the formula:

A = QR

where Q is an orthogonal matrix and R is an upper triangular matrix.

The orthogonal basis for A is given as:

Q = ⎡

−10 2 −6 16 2

3 3 −3 0 3

6 0 6 6 0

0 5 0 0 −5

To find matrix R, we can use the formula:

R = Q^T * A

where Q^T is the transpose of matrix Q.

Calculating the transpose of Q:

Q^T = ⎡

−10 3 6 0

2 3 0 5

−6 −3 6 0

16 0 6 0

2 3 0 −5

Calculating R:

R = Q^T * A = ⎡

−10 3 6 0

2 3 0 5

−6 −3 6 0

16 0 6 0

2 3 0 −5

⎦ * ⎡

−10 2 −6 16 2

−4 8 −12 16 8

−1 5 −3 22 5

−1 10 −3 22 0

Performing the matrix multiplication:

R = ⎡

446 -139 189 100

0 14 0 -42

0 0 0 0

0 0 0 0

Therefore, the QR factorization of matrix A is:

A = QR, where

Q = ⎡

−10 2 −6 16 2

3 3 −3 0 3

6 0 6 6 0

0 5 0 0 −5

R = ⎡

446 -139 189 100

0 14 0 -42

0 0 0 0

0 0 0

User Sunghoon
by
8.7k points