(a) Show that A is an n x n matrix and det(A) # 0, then the projection matrix P A(ATA)-¹A¹ is the nxn identity matrix I (matrix with 1 on the diagonal and 0 outside of the diagonal).

College Algebra
7th Edition
ISBN:9781305115545
Author:James Stewart, Lothar Redlin, Saleem Watson
Publisher:James Stewart, Lothar Redlin, Saleem Watson
Chapter6: Matrices And Determinants
Section: Chapter Questions
Problem 66E: Distribution of Cash An ATM at a bank in Qualicum Beach, British Columbia, dispenses $20 and $50...
icon
Related questions
Question
Projection Matrix
(a) Show that A is an n x n matrix and det(A) 0, then the projection matrix P
A(ATA)-¹AT is the nxn identity matrix I (matrix with 1 on the diagonal and 0 outside
of the diagonal).
(b) Consider the system equations r = 4 and r = 6. Obviously this system of equations
does not have an exact solution. Represent the system of equations as Av = b where
A = [1,1], v = [r], and b = [4,6]T. Find the projection matrix P. Show graphically
the point b (the first coordinate on the z-axis and the second coordinate on the y-axis)
and the point Pb. Show the set of points v € R2x1 such that Pu= v. What is the value
of a that solves Az = Pb?
(c) Repeat the previous exercise for the system of equations r = 4 and 2x = 12. Keep in
mind that you will obtain a different projection matrix. What is the value of a that
solves Ax = Pb?
(d) Find the approximate solution of the system of equations (using the projection matrix)
[1 2]
34
5 6
] [C]
10
15
Transcribed Image Text:Projection Matrix (a) Show that A is an n x n matrix and det(A) 0, then the projection matrix P A(ATA)-¹AT is the nxn identity matrix I (matrix with 1 on the diagonal and 0 outside of the diagonal). (b) Consider the system equations r = 4 and r = 6. Obviously this system of equations does not have an exact solution. Represent the system of equations as Av = b where A = [1,1], v = [r], and b = [4,6]T. Find the projection matrix P. Show graphically the point b (the first coordinate on the z-axis and the second coordinate on the y-axis) and the point Pb. Show the set of points v € R2x1 such that Pu= v. What is the value of a that solves Az = Pb? (c) Repeat the previous exercise for the system of equations r = 4 and 2x = 12. Keep in mind that you will obtain a different projection matrix. What is the value of a that solves Ax = Pb? (d) Find the approximate solution of the system of equations (using the projection matrix) [1 2] 34 5 6 ] [C] 10 15
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps

Blurred answer
Similar questions
Recommended textbooks for you
College Algebra
College Algebra
Algebra
ISBN:
9781305115545
Author:
James Stewart, Lothar Redlin, Saleem Watson
Publisher:
Cengage Learning
Algebra and Trigonometry (MindTap Course List)
Algebra and Trigonometry (MindTap Course List)
Algebra
ISBN:
9781305071742
Author:
James Stewart, Lothar Redlin, Saleem Watson
Publisher:
Cengage Learning
Elementary Linear Algebra (MindTap Course List)
Elementary Linear Algebra (MindTap Course List)
Algebra
ISBN:
9781305658004
Author:
Ron Larson
Publisher:
Cengage Learning
College Algebra
College Algebra
Algebra
ISBN:
9781337282291
Author:
Ron Larson
Publisher:
Cengage Learning
College Algebra (MindTap Course List)
College Algebra (MindTap Course List)
Algebra
ISBN:
9781305652231
Author:
R. David Gustafson, Jeff Hughes
Publisher:
Cengage Learning
Algebra & Trigonometry with Analytic Geometry
Algebra & Trigonometry with Analytic Geometry
Algebra
ISBN:
9781133382119
Author:
Swokowski
Publisher:
Cengage