Lecture 11: Eigenvalues and Eigenvectors
|
|
- Augustine Leslie Flowers
- 6 years ago
- Views:
Transcription
1 Lecture : Eigenvalues and Eigenvectors De nition.. Let A be a square matrix (or linear transformation). A number λ is called an eigenvalue of A if there exists a non-zero vector u such that A u λ u. () In the above de nition, the vector u is called an eigenvector associated with this eigenvalue λ. The set of all eigenvectors associated with λforms a subspace, and is called the eigenspace associated with λ. Geometrically, if we view any n n matrix A as a linear transformation T. Then the fact that u is an eigenvector associated with an eigenvalue λ means u is an invariant direction under T. In other words, the linear transformation T does not change the direction of u : u and T u either have the same direction (λ > ) or opposite direction (λ< ). The eigenvalue is the factor of contraction (jλj < ) or extension (jλj > ). Remarks. () u 6 is crucial, since u always satis es Equ (). () If u is an eigenvector for λ, then so is c u for any constant c. () Geometrically, in D, eigenvectors of A are directions that are unchanged under linear transformation A. We observe from Equ () that λ is an eigenvalue i Equ () has a non-trivial solution. Since Equ () can be written as (A λi) u A u λ u, () it follows λ is an eigenvalue i Equ () has a non-trivial solution. By the inverse matrix theorem, Equ () has a non-trivial solution i det (A λi). () We conclude that λ is an eigenvalue i Equ () holds. We call Equ () "Characteristic Equation" of A. The eigenspace, the subspace of all eigenvectors associated with λ, is eigenspace Null (A λi). ² Finding eigenvalues and all independent eigenvectors: Step. Solve Characteristic Equ () for λ. Step. For each λ, nd a basis for the eigenspace Null (A λi) (i.e., solution set of Equ ()). Example.. Find all eigenvalues and their eigenspace for A. Solution: A λi λ λ λ. λ λ
2 The characteristic equation is We nd eigenvalues det (A λi) ( λ) ( λ) ( ), λ λ+, (λ ) (λ ). λ, λ. We next nd eigenvectors associated with each eigenvalue. For λ, x x (A λ I) x, x x or x x. The parametric vector form of solution set for (A λ I) x : x x x x x x. basis of Null (A I) :. This is only (linearly independent) eigenvector for λ. The last step can be done slightly di erently as follows. From solutions (for (A λ I) x ) x x, we know there is only one free variable x. Therefore, there is only one vector in any basis. To nd it, we take x to be any nonzero number, for instance, x, and compute x x. We obtain x λ, u. x For λ, we nd or (A λ I) x x x x x. x, x To nd a basis, we take x. Then x, and a pair of eigenvalue and eigenvector λ, u.
3 Example.. Given that is an eigenvalue for A Find a basis of its eigenspace. Solution: A I ! Therefore, (A I) x becomes x x + 6x, or x x + 6x, (4) where we select x and x as free variables only to avoid fractions. Solution set in parametric form is x 4 x x x 5 4x + 6x 5 x x A basis for the eigenspace: x x u 45 and u 465. Another way of nding a basis for Null (A λi) Null (A I) may be a little easier. From Equ (4), we know that x an x are free variables. Choosing (x, x ) (, ) and (, ), respectively, we nd x, x ) x ) u 4 5 x, x ) x 6 ) u Example.. Find eigenvalues: (a) 6 λ 6 A 4 65, A λi 4 λ 6 5. λ det (A λi) ( λ) ( λ) ( λ)
4 The eigenvalues are,,, exactly the diagonal elements. (b) B 4 4 5, B λi 4 4 λ λ λ det (B λi) (4 λ) ( λ). The eigenvalues are 4,, 4 (4 is a double root), exactly the diagonal elements. Theorem.. () The eigenvalues of a triangle matrix are its diagonal elements. () Eigenvectors for di erent eigenvalues are linearly independent. More precisely, suppose that λ, λ,..., λ p are p di erent eigenvalues of a matrix A. Then, the set consisting of a basis of Null (A λ I), a basis of Null (A λ I),..., a basis of Null (A λ p I) is linearly independent. Proof. () For simplicity, we assume p : λ 6 λ are two di erent eigenvalues. Suppose that u is an eigenvector of λ and u is an eigenvector of λ To show independence, we need to show that the only solution to x u + x u is x x. Indeed, if x 6, then We now apply A to the above equation. It leads to u x x u. (5) A u x x A u ) λ u x x λ u. (6) Equ (5) and Equ (6) are contradictory to each other: by Equ (5), or Equ (5) ) λ u x x λ u Equ (6) ) λ u x x λ u, x x λ u λ u x x λ u. Therefor λ λ, a contradiction to the assumption that they are di erent eigenvalues. ² Characteristic Polynomials 4
5 We know that the key to nd eigenvalues and eigenvectors is to solve the Characteristic Equation () det (A λi). For matrix, So a λ b A λi. c d λ det (A λi) (a λ) (d λ) bc λ + ( a d) λ+ (ad bc) is a quadratic function (i.e., a polynomial of degree ). In general, for any n n matrix A, a λ a a n A λi 6 a a λ a n 4 5. a n a n a nn λ We may expand the determinant along the rst row to get det (A λi) (a λ) det 4 a λ a n a n a nn λ By induction, we see that det (A λi) is a polynomial of degree n.we called this polynomial the characteristic polynomial of A. Consequently, there are total of n (the number of rows in the matrix A) eigenvalues (real or complex, after taking account for multiplicity). Finding roots for higher order polynomials may be very challenging. Example.4. Find all eigenvalues for Solution: A λi 5 6 A λ 6 6 λ λ 4 5, λ λ 8 det (A λi) (5 λ) det 4 5 λ 4 5 λ 5 λ 4 (5 λ) ( λ) det λ (5 λ) ( λ) [(5 λ) ( λ) 4]. 5
6 There are 4 roots: (5 λ) ) λ 5 ( λ) ) λ (5 λ) ( λ) 4 ) λ 6λ+ ) λ 6 p 6 4 p. We know that we can computer determinants using elementary row operations. One may ask: Can we use elementary row operations to nd eigenvalues? More speci cally, we have Question: Suppose that B is obtained from A by elementary row operations. Do A and B has the same eigenvalues? (Ans: No) Example.5. R A +R!R! B A has eigenvalues and. For B, the characteristic equation is λ det (B λi) λ The eigenvalues are ( λ) ( λ) λ 4λ+. λ 4 p p 8 p. This example show that row operation may completely change eigenvalues. De nition.. Two n n matrices A and B are called similar, and is denoted as A» B, if there exists an invertible matrix P such that A P BP. Theorem.. If A and B are similar, then they have exact the same characteristic polynomial and consequently the same eigenvalues. Indeed, if A P BP, then P (B λi) P P BP λp IP (A λi). Therefore, det (A λi) det P (B λi) P det (P ) det (B λi) det P det (B λi). Example.6. Find eigenvalues of A if 5 6 A» B Solution: Eigenvalues of B are λ 5,, 5, 4. These are also the eigenvalues of A. 6
7 Caution: If A» B, and if λ is an eigenvalue for A and B, then an corresponding eigenvector for A may not be an eigenvector for B. In other words, two similar matrices A and B have the same eigenvalues but di erent eigenvectors. Example.. Though row operation alone will not preserve eigenvalues, a pair of row and column operation do maintain similarity. We rst observe that if P is a type elementary matrix (row replacement), ar P +R!R Ã, a then its inverse P is a type (column) elementary matrix obtained from the identity matrix by an elementary column operation that is of the same kind with "opposite sign" to the previous row operation, i.e., P C ac!c Ã. a We call the column operation is "inverse" to the row operation C ac! C R + ar! R. Now we perform a row operation on A followed immediately by the column operation inverse to the row operation R A +R!R! (left multiply by P ) C C!C! B (right multiply by P.) We can verify that A and B are similar through P (with a ) P AP. Now, λ is an eigenvalue. Then, (A ) u ) u is an eigenvector for A.
8 But In fact, (B ) u ) u is NOT an eigenvector for B. (B ) v. So, v is an eigenvector for B. This example shows that. Row operation alone will not preserve eigenvalues.. Two similar matrices share the same characteristics polynomial and same eigenvalues. But they have di erent eigenvectors. ² Homework #.. Find eigenvalues if 8 (a) A» (b) B» Find eigenvalues and a basis of each eigenspace. 4 (a) A. 9 (b) B
9 . Find a basis of the eigenspace associated with eigenvalue λ for 4 A Determine true or false. Reason your answers. (a) If A x λ x, then λ is an eigenvalue of A. (b) A is invertible i is not an eigenvalue. (c) If A» B, then A and B has the same eigenvalues and eigenspaces. (d) If A and B have the same eigenvalues, then they have the same characteristic polynomial. (e) If det A det B, then A is similar to B. 9
Lecture 12: Diagonalization
Lecture : Diagonalization A square matrix D is called diagonal if all but diagonal entries are zero: a a D a n 5 n n. () Diagonal matrices are the simplest matrices that are basically equivalent to vectors
More informationRemark By definition, an eigenvector must be a nonzero vector, but eigenvalue could be zero.
Sec 6 Eigenvalues and Eigenvectors Definition An eigenvector of an n n matrix A is a nonzero vector x such that A x λ x for some scalar λ A scalar λ is called an eigenvalue of A if there is a nontrivial
More informationTherefore, A and B have the same characteristic polynomial and hence, the same eigenvalues.
Similar Matrices and Diagonalization Page 1 Theorem If A and B are n n matrices, which are similar, then they have the same characteristic equation and hence the same eigenvalues. Proof Let A and B be
More informationDimension. Eigenvalue and eigenvector
Dimension. Eigenvalue and eigenvector Math 112, week 9 Goals: Bases, dimension, rank-nullity theorem. Eigenvalue and eigenvector. Suggested Textbook Readings: Sections 4.5, 4.6, 5.1, 5.2 Week 9: Dimension,
More informationRemark 1 By definition, an eigenvector must be a nonzero vector, but eigenvalue could be zero.
Sec 5 Eigenvectors and Eigenvalues In this chapter, vector means column vector Definition An eigenvector of an n n matrix A is a nonzero vector x such that A x λ x for some scalar λ A scalar λ is called
More informationDefinition (T -invariant subspace) Example. Example
Eigenvalues, Eigenvectors, Similarity, and Diagonalization We now turn our attention to linear transformations of the form T : V V. To better understand the effect of T on the vector space V, we begin
More informationCalculating determinants for larger matrices
Day 26 Calculating determinants for larger matrices We now proceed to define det A for n n matrices A As before, we are looking for a function of A that satisfies the product formula det(ab) = det A det
More informationDIAGONALIZATION. In order to see the implications of this definition, let us consider the following example Example 1. Consider the matrix
DIAGONALIZATION Definition We say that a matrix A of size n n is diagonalizable if there is a basis of R n consisting of eigenvectors of A ie if there are n linearly independent vectors v v n such that
More informationDiagonalization of Matrix
of Matrix King Saud University August 29, 2018 of Matrix Table of contents 1 2 of Matrix Definition If A M n (R) and λ R. We say that λ is an eigenvalue of the matrix A if there is X R n \ {0} such that
More informationMath 3191 Applied Linear Algebra
Math 9 Applied Linear Algebra Lecture 9: Diagonalization Stephen Billups University of Colorado at Denver Math 9Applied Linear Algebra p./9 Section. Diagonalization The goal here is to develop a useful
More informationChapter 5. Eigenvalues and Eigenvectors
Chapter 5 Eigenvalues and Eigenvectors Section 5. Eigenvectors and Eigenvalues Motivation: Difference equations A Biology Question How to predict a population of rabbits with given dynamics:. half of the
More information(a) II and III (b) I (c) I and III (d) I and II and III (e) None are true.
1 Which of the following statements is always true? I The null space of an m n matrix is a subspace of R m II If the set B = {v 1,, v n } spans a vector space V and dimv = n, then B is a basis for V III
More informationMATH 221, Spring Homework 10 Solutions
MATH 22, Spring 28 - Homework Solutions Due Tuesday, May Section 52 Page 279, Problem 2: 4 λ A λi = and the characteristic polynomial is det(a λi) = ( 4 λ)( λ) ( )(6) = λ 6 λ 2 +λ+2 The solutions to the
More informationQuestion: Given an n x n matrix A, how do we find its eigenvalues? Idea: Suppose c is an eigenvalue of A, then what is the determinant of A-cI?
Section 5. The Characteristic Polynomial Question: Given an n x n matrix A, how do we find its eigenvalues? Idea: Suppose c is an eigenvalue of A, then what is the determinant of A-cI? Property The eigenvalues
More informationEigenvalue and Eigenvector Homework
Eigenvalue and Eigenvector Homework Olena Bormashenko November 4, 2 For each of the matrices A below, do the following:. Find the characteristic polynomial of A, and use it to find all the eigenvalues
More informationEigenvalues and Eigenvectors 7.2 Diagonalization
Eigenvalues and Eigenvectors 7.2 Diagonalization November 8 Goals Suppose A is square matrix of order n. Provide necessary and sufficient condition when there is an invertible matrix P such that P 1 AP
More informationCity Suburbs. : population distribution after m years
Section 5.3 Diagonalization of Matrices Definition Example: stochastic matrix To City Suburbs From City Suburbs.85.03 = A.15.97 City.15.85 Suburbs.97.03 probability matrix of a sample person s residence
More information1. In this problem, if the statement is always true, circle T; otherwise, circle F.
Math 1553, Extra Practice for Midterm 3 (sections 45-65) Solutions 1 In this problem, if the statement is always true, circle T; otherwise, circle F a) T F If A is a square matrix and the homogeneous equation
More informationand let s calculate the image of some vectors under the transformation T.
Chapter 5 Eigenvalues and Eigenvectors 5. Eigenvalues and Eigenvectors Let T : R n R n be a linear transformation. Then T can be represented by a matrix (the standard matrix), and we can write T ( v) =
More information1. What is the determinant of the following matrix? a 1 a 2 4a 3 2a 2 b 1 b 2 4b 3 2b c 1. = 4, then det
What is the determinant of the following matrix? 3 4 3 4 3 4 4 3 A 0 B 8 C 55 D 0 E 60 If det a a a 3 b b b 3 c c c 3 = 4, then det a a 4a 3 a b b 4b 3 b c c c 3 c = A 8 B 6 C 4 D E 3 Let A be an n n matrix
More information235 Final exam review questions
5 Final exam review questions Paul Hacking December 4, 0 () Let A be an n n matrix and T : R n R n, T (x) = Ax the linear transformation with matrix A. What does it mean to say that a vector v R n is an
More informationMath 18, Linear Algebra, Lecture C00, Spring 2017 Review and Practice Problems for Final Exam
Math 8, Linear Algebra, Lecture C, Spring 7 Review and Practice Problems for Final Exam. The augmentedmatrix of a linear system has been transformed by row operations into 5 4 8. Determine if the system
More informationMATH 20F: LINEAR ALGEBRA LECTURE B00 (T. KEMP)
MATH 20F: LINEAR ALGEBRA LECTURE B00 (T KEMP) Definition 01 If T (x) = Ax is a linear transformation from R n to R m then Nul (T ) = {x R n : T (x) = 0} = Nul (A) Ran (T ) = {Ax R m : x R n } = {b R m
More informationDiagonalization. MATH 322, Linear Algebra I. J. Robert Buchanan. Spring Department of Mathematics
Diagonalization MATH 322, Linear Algebra I J. Robert Buchanan Department of Mathematics Spring 2015 Motivation Today we consider two fundamental questions: Given an n n matrix A, does there exist a basis
More informationMath 110 Linear Algebra Midterm 2 Review October 28, 2017
Math 11 Linear Algebra Midterm Review October 8, 17 Material Material covered on the midterm includes: All lectures from Thursday, Sept. 1st to Tuesday, Oct. 4th Homeworks 9 to 17 Quizzes 5 to 9 Sections
More informationLinear Algebra: Matrix Eigenvalue Problems
CHAPTER8 Linear Algebra: Matrix Eigenvalue Problems Chapter 8 p1 A matrix eigenvalue problem considers the vector equation (1) Ax = λx. 8.0 Linear Algebra: Matrix Eigenvalue Problems Here A is a given
More informationMAT 1302B Mathematical Methods II
MAT 1302B Mathematical Methods II Alistair Savage Mathematics and Statistics University of Ottawa Winter 2015 Lecture 19 Alistair Savage (uottawa) MAT 1302B Mathematical Methods II Winter 2015 Lecture
More informationDiagonalization. Hung-yi Lee
Diagonalization Hung-yi Lee Review If Av = λv (v is a vector, λ is a scalar) v is an eigenvector of A excluding zero vector λ is an eigenvalue of A that corresponds to v Eigenvectors corresponding to λ
More informationA = 3 1. We conclude that the algebraic multiplicity of the eigenvalues are both one, that is,
65 Diagonalizable Matrices It is useful to introduce few more concepts, that are common in the literature Definition 65 The characteristic polynomial of an n n matrix A is the function p(λ) det(a λi) Example
More informationEigenvalues, Eigenvectors, and Diagonalization
Math 240 TA: Shuyi Weng Winter 207 February 23, 207 Eigenvalues, Eigenvectors, and Diagonalization The concepts of eigenvalues, eigenvectors, and diagonalization are best studied with examples. We will
More informationChapter 5 Eigenvalues and Eigenvectors
Chapter 5 Eigenvalues and Eigenvectors Outline 5.1 Eigenvalues and Eigenvectors 5.2 Diagonalization 5.3 Complex Vector Spaces 2 5.1 Eigenvalues and Eigenvectors Eigenvalue and Eigenvector If A is a n n
More informationLinear algebra I Homework #1 due Thursday, Oct Show that the diagonals of a square are orthogonal to one another.
Homework # due Thursday, Oct. 0. Show that the diagonals of a square are orthogonal to one another. Hint: Place the vertices of the square along the axes and then introduce coordinates. 2. Find the equation
More informationHW2 - Due 01/30. Each answer must be mathematically justified. Don t forget your name.
HW2 - Due 0/30 Each answer must be mathematically justified. Don t forget your name. Problem. Use the row reduction algorithm to find the inverse of the matrix 0 0, 2 3 5 if it exists. Double check your
More informationYORK UNIVERSITY. Faculty of Science Department of Mathematics and Statistics MATH M Test #1. July 11, 2013 Solutions
YORK UNIVERSITY Faculty of Science Department of Mathematics and Statistics MATH 222 3. M Test # July, 23 Solutions. For each statement indicate whether it is always TRUE or sometimes FALSE. Note: For
More informationStudy Guide for Linear Algebra Exam 2
Study Guide for Linear Algebra Exam 2 Term Vector Space Definition A Vector Space is a nonempty set V of objects, on which are defined two operations, called addition and multiplication by scalars (real
More informationEigenvalues and Eigenvectors
5 Eigenvalues and Eigenvectors 5.2 THE CHARACTERISTIC EQUATION DETERMINANATS nn Let A be an matrix, let U be any echelon form obtained from A by row replacements and row interchanges (without scaling),
More informationLINEAR ALGEBRA 1, 2012-I PARTIAL EXAM 3 SOLUTIONS TO PRACTICE PROBLEMS
LINEAR ALGEBRA, -I PARTIAL EXAM SOLUTIONS TO PRACTICE PROBLEMS Problem (a) For each of the two matrices below, (i) determine whether it is diagonalizable, (ii) determine whether it is orthogonally diagonalizable,
More informationMTH 464: Computational Linear Algebra
MTH 464: Computational Linear Algebra Lecture Outlines Exam 2 Material Prof. M. Beauregard Department of Mathematics & Statistics Stephen F. Austin State University March 2, 2018 Linear Algebra (MTH 464)
More informationLecture 18: Section 4.3
Lecture 18: Section 4.3 Shuanglin Shao November 6, 2013 Linear Independence and Linear Dependence. We will discuss linear independence of vectors in a vector space. Definition. If S = {v 1, v 2,, v r }
More informationProblem 1: Solving a linear equation
Math 38 Practice Final Exam ANSWERS Page Problem : Solving a linear equation Given matrix A = 2 2 3 7 4 and vector y = 5 8 9. (a) Solve Ax = y (if the equation is consistent) and write the general solution
More informationLINEAR ALGEBRA REVIEW
LINEAR ALGEBRA REVIEW SPENCER BECKER-KAHN Basic Definitions Domain and Codomain. Let f : X Y be any function. This notation means that X is the domain of f and Y is the codomain of f. This means that for
More informationAnnouncements Wednesday, November 01
Announcements Wednesday, November 01 WeBWorK 3.1, 3.2 are due today at 11:59pm. The quiz on Friday covers 3.1, 3.2. My office is Skiles 244. Rabinoffice hours are Monday, 1 3pm and Tuesday, 9 11am. Section
More informationEigenvalues and Eigenvectors. Prepared by Vince Zaccone For Campus Learning Assistance Services at UCSB
Eigenvalues and Eigenvectors Consider the equation A x = λ x, where A is an nxn matrix. We call x (must be non-zero) an eigenvector of A if this equation can be solved for some value of λ. We call λ an
More informationSolutions to Final Practice Problems Written by Victoria Kala Last updated 12/5/2015
Solutions to Final Practice Problems Written by Victoria Kala vtkala@math.ucsb.edu Last updated /5/05 Answers This page contains answers only. See the following pages for detailed solutions. (. (a x. See
More information4. Linear transformations as a vector space 17
4 Linear transformations as a vector space 17 d) 1 2 0 0 1 2 0 0 1 0 0 0 1 2 3 4 32 Let a linear transformation in R 2 be the reflection in the line = x 2 Find its matrix 33 For each linear transformation
More information1. Linear systems of equations. Chapters 7-8: Linear Algebra. Solution(s) of a linear system of equations (continued)
1 A linear system of equations of the form Sections 75, 78 & 81 a 11 x 1 + a 12 x 2 + + a 1n x n = b 1 a 21 x 1 + a 22 x 2 + + a 2n x n = b 2 a m1 x 1 + a m2 x 2 + + a mn x n = b m can be written in matrix
More informationGlossary of Linear Algebra Terms. Prepared by Vince Zaccone For Campus Learning Assistance Services at UCSB
Glossary of Linear Algebra Terms Basis (for a subspace) A linearly independent set of vectors that spans the space Basic Variable A variable in a linear system that corresponds to a pivot column in the
More informationMath 4A Notes. Written by Victoria Kala Last updated June 11, 2017
Math 4A Notes Written by Victoria Kala vtkala@math.ucsb.edu Last updated June 11, 2017 Systems of Linear Equations A linear equation is an equation that can be written in the form a 1 x 1 + a 2 x 2 +...
More informationEigenvalues and Eigenvectors
Eigenvalues and Eigenvectors week -2 Fall 26 Eigenvalues and eigenvectors The most simple linear transformation from R n to R n may be the transformation of the form: T (x,,, x n ) (λ x, λ 2,, λ n x n
More informationMATH 423 Linear Algebra II Lecture 20: Geometry of linear transformations. Eigenvalues and eigenvectors. Characteristic polynomial.
MATH 423 Linear Algebra II Lecture 20: Geometry of linear transformations. Eigenvalues and eigenvectors. Characteristic polynomial. Geometric properties of determinants 2 2 determinants and plane geometry
More informationMath 205, Summer I, Week 4b:
Math 205, Summer I, 2016 Week 4b: Chapter 5, Sections 6, 7 and 8 (5.5 is NOT on the syllabus) 5.6 Eigenvalues and Eigenvectors 5.7 Eigenspaces, nondefective matrices 5.8 Diagonalization [*** See next slide
More information(b) If a multiple of one row of A is added to another row to produce B then det(b) =det(a).
.(5pts) Let B = 5 5. Compute det(b). (a) (b) (c) 6 (d) (e) 6.(5pts) Determine which statement is not always true for n n matrices A and B. (a) If two rows of A are interchanged to produce B, then det(b)
More informationJordan Canonical Form Homework Solutions
Jordan Canonical Form Homework Solutions For each of the following, put the matrix in Jordan canonical form and find the matrix S such that S AS = J. [ ]. A = A λi = λ λ = ( λ) = λ λ = λ =, Since we have
More informationMath 217: Eigenspaces and Characteristic Polynomials Professor Karen Smith
Math 217: Eigenspaces and Characteristic Polynomials Professor Karen Smith (c)2015 UM Math Dept licensed under a Creative Commons By-NC-SA 4.0 International License. Definition: Let V T V be a linear transformation.
More informationLecture 22: Section 4.7
Lecture 22: Section 47 Shuanglin Shao December 2, 213 Row Space, Column Space, and Null Space Definition For an m n, a 11 a 12 a 1n a 21 a 22 a 2n A = a m1 a m2 a mn, the vectors r 1 = [ a 11 a 12 a 1n
More informationAnnouncements Monday, November 06
Announcements Monday, November 06 This week s quiz: covers Sections 5 and 52 Midterm 3, on November 7th (next Friday) Exam covers: Sections 3,32,5,52,53 and 55 Section 53 Diagonalization Motivation: Difference
More information2 Eigenvectors and Eigenvalues in abstract spaces.
MA322 Sathaye Notes on Eigenvalues Spring 27 Introduction In these notes, we start with the definition of eigenvectors in abstract vector spaces and follow with the more common definition of eigenvectors
More informationThen x 1,..., x n is a basis as desired. Indeed, it suffices to verify that it spans V, since n = dim(v ). We may write any v V as r
Practice final solutions. I did not include definitions which you can find in Axler or in the course notes. These solutions are on the terse side, but would be acceptable in the final. However, if you
More informationEcon Slides from Lecture 7
Econ 205 Sobel Econ 205 - Slides from Lecture 7 Joel Sobel August 31, 2010 Linear Algebra: Main Theory A linear combination of a collection of vectors {x 1,..., x k } is a vector of the form k λ ix i for
More information(a) only (ii) and (iv) (b) only (ii) and (iii) (c) only (i) and (ii) (d) only (iv) (e) only (i) and (iii)
. Which of the following are Vector Spaces? (i) V = { polynomials of the form q(t) = t 3 + at 2 + bt + c : a b c are real numbers} (ii) V = {at { 2 + b : a b are real numbers} } a (iii) V = : a 0 b is
More information5.3.5 The eigenvalues are 3, 2, 3 (i.e., the diagonal entries of D) with corresponding eigenvalues. Null(A 3I) = Null( ), 0 0
535 The eigenvalues are 3,, 3 (ie, the diagonal entries of D) with corresponding eigenvalues,, 538 The matrix is upper triangular so the eigenvalues are simply the diagonal entries, namely 3, 3 The corresponding
More informationEIGENVALUES AND EIGENVECTORS 3
EIGENVALUES AND EIGENVECTORS 3 1. Motivation 1.1. Diagonal matrices. Perhaps the simplest type of linear transformations are those whose matrix is diagonal (in some basis). Consider for example the matrices
More informationComputationally, diagonal matrices are the easiest to work with. With this idea in mind, we introduce similarity:
Diagonalization We have seen that diagonal and triangular matrices are much easier to work with than are most matrices For example, determinants and eigenvalues are easy to compute, and multiplication
More informationReview problems for MA 54, Fall 2004.
Review problems for MA 54, Fall 2004. Below are the review problems for the final. They are mostly homework problems, or very similar. If you are comfortable doing these problems, you should be fine on
More informationOHSx XM511 Linear Algebra: Solutions to Online True/False Exercises
This document gives the solutions to all of the online exercises for OHSx XM511. The section ( ) numbers refer to the textbook. TYPE I are True/False. Answers are in square brackets [. Lecture 02 ( 1.1)
More informationMATH 1553 PRACTICE MIDTERM 3 (VERSION B)
MATH 1553 PRACTICE MIDTERM 3 (VERSION B) Name Section 1 2 3 4 5 Total Please read all instructions carefully before beginning. Each problem is worth 10 points. The maximum score on this exam is 50 points.
More informationMath Final December 2006 C. Robinson
Math 285-1 Final December 2006 C. Robinson 2 5 8 5 1 2 0-1 0 1. (21 Points) The matrix A = 1 2 2 3 1 8 3 2 6 has the reduced echelon form U = 0 0 1 2 0 0 0 0 0 1. 2 6 1 0 0 0 0 0 a. Find a basis for the
More informationSOLUTIONS: ASSIGNMENT Use Gaussian elimination to find the determinant of the matrix. = det. = det = 1 ( 2) 3 6 = 36. v 4.
SOLUTIONS: ASSIGNMENT 9 66 Use Gaussian elimination to find the determinant of the matrix det 1 1 4 4 1 1 1 1 8 8 = det = det 0 7 9 0 0 0 6 = 1 ( ) 3 6 = 36 = det = det 0 0 6 1 0 0 0 6 61 Consider a 4
More informationAnnouncements Wednesday, November 01
Announcements Wednesday, November 01 WeBWorK 3.1, 3.2 are due today at 11:59pm. The quiz on Friday covers 3.1, 3.2. My office is Skiles 244. Rabinoffice hours are Monday, 1 3pm and Tuesday, 9 11am. Section
More informationSUPPLEMENT TO CHAPTERS VII/VIII
SUPPLEMENT TO CHAPTERS VII/VIII The characteristic polynomial of an operator Let A M n,n (F ) be an n n-matrix Then the characteristic polynomial of A is defined by: C A (x) = det(xi A) where I denotes
More informationEXAM. Exam #3. Math 2360, Spring April 24, 2001 ANSWERS
EXAM Exam #3 Math 2360, Spring 200 April 24, 200 ANSWERS i 40 pts Problem In this problem, we will work in the vectorspace P 3 = { ax 2 + bx + c a, b, c R }, the space of polynomials of degree less than
More informationMath 308 Practice Final Exam Page and vector y =
Math 308 Practice Final Exam Page Problem : Solving a linear equation 2 0 2 5 Given matrix A = 3 7 0 0 and vector y = 8. 4 0 0 9 (a) Solve Ax = y (if the equation is consistent) and write the general solution
More informationEigenvalues and Eigenvectors
CHAPTER Eigenvalues and Eigenvectors CHAPTER CONTENTS. Eigenvalues and Eigenvectors 9. Diagonalization. Complex Vector Spaces.4 Differential Equations 6. Dynamical Systems and Markov Chains INTRODUCTION
More informationHomework Set #8 Solutions
Exercises.2 (p. 19) Homework Set #8 Solutions Assignment: Do #6, 8, 12, 14, 2, 24, 26, 29, 0, 2, 4, 5, 6, 9, 40, 42 6. Reducing the matrix to echelon form: 1 5 2 1 R2 R2 R1 1 5 0 18 12 2 1 R R 2R1 1 5
More informationMath Matrix Theory - Spring 2012
Math 440 - Matrix Theory - Spring 202 HW #2 Solutions Which of the following are true? Why? If not true, give an example to show that If true, give your reasoning (a) Inverse of an elementary matrix is
More informationRecall : Eigenvalues and Eigenvectors
Recall : Eigenvalues and Eigenvectors Let A be an n n matrix. If a nonzero vector x in R n satisfies Ax λx for a scalar λ, then : The scalar λ is called an eigenvalue of A. The vector x is called an eigenvector
More informationc c c c c c c c c c a 3x3 matrix C= has a determinant determined by
Linear Algebra Determinants and Eigenvalues Introduction: Many important geometric and algebraic properties of square matrices are associated with a single real number revealed by what s known as the determinant.
More informationMA 265 FINAL EXAM Fall 2012
MA 265 FINAL EXAM Fall 22 NAME: INSTRUCTOR S NAME:. There are a total of 25 problems. You should show work on the exam sheet, and pencil in the correct answer on the scantron. 2. No books, notes, or calculators
More informationEigenspaces. (c) Find the algebraic multiplicity and the geometric multiplicity for the eigenvaules of A.
Eigenspaces 1. (a) Find all eigenvalues and eigenvectors of A = (b) Find the corresponding eigenspaces. [ ] 1 1 1 Definition. If A is an n n matrix and λ is a scalar, the λ-eigenspace of A (usually denoted
More informationEigenvalues and Eigenvectors
5 Eigenvalues and Eigenvectors 5.2 THE CHARACTERISTIC EQUATION DETERMINANATS n n Let A be an matrix, let U be any echelon form obtained from A by row replacements and row interchanges (without scaling),
More informationLU Factorization. A m x n matrix A admits an LU factorization if it can be written in the form of A = LU
LU Factorization A m n matri A admits an LU factorization if it can be written in the form of Where, A = LU L : is a m m lower triangular matri with s on the diagonal. The matri L is invertible and is
More informationAnnouncements Monday, October 29
Announcements Monday, October 29 WeBWorK on determinents due on Wednesday at :59pm. The quiz on Friday covers 5., 5.2, 5.3. My office is Skiles 244 and Rabinoffice hours are: Mondays, 2 pm; Wednesdays,
More informationMath 1553, Introduction to Linear Algebra
Learning goals articulate what students are expected to be able to do in a course that can be measured. This course has course-level learning goals that pertain to the entire course, and section-level
More informationWarm-up. True or false? Baby proof. 2. The system of normal equations for A x = y has solutions iff A x = y has solutions
Warm-up True or false? 1. proj u proj v u = u 2. The system of normal equations for A x = y has solutions iff A x = y has solutions 3. The normal equations are always consistent Baby proof 1. Let A be
More informationLinear algebra I Homework #1 due Thursday, Oct. 5
Homework #1 due Thursday, Oct. 5 1. Show that A(5,3,4), B(1,0,2) and C(3, 4,4) are the vertices of a right triangle. 2. Find the equation of the plane that passes through the points A(2,4,3), B(2,3,5),
More informationDesigning Information Devices and Systems I Discussion 4B
Last Updated: 29-2-2 9:56 EECS 6A Spring 29 Designing Information Devices and Systems I Discussion 4B Reference Definitions: Matrices and Linear (In)Dependence We ve seen that the following statements
More informationSolutions Problem Set 8 Math 240, Fall
Solutions Problem Set 8 Math 240, Fall 2012 5.6 T/F.2. True. If A is upper or lower diagonal, to make det(a λi) 0, we need product of the main diagonal elements of A λi to be 0, which means λ is one of
More informationPart I True or False. (One point each. A wrong answer is subject to one point deduction.)
FACULTY OF ENGINEERING CHULALONGKORN UNIVERSITY 21121 Computer Engineering Mathematics YEAR II, Second Semester, Final Examination, March 3, 214, 13: 16: Name ID 2 1 CR58 Instructions 1. There are 43 questions,
More informationPRACTICE PROBLEMS FOR THE FINAL
PRACTICE PROBLEMS FOR THE FINAL Here are a slew of practice problems for the final culled from old exams:. Let P be the vector space of polynomials of degree at most. Let B = {, (t ), t + t }. (a) Show
More informationProperties of Linear Transformations from R n to R m
Properties of Linear Transformations from R n to R m MATH 322, Linear Algebra I J. Robert Buchanan Department of Mathematics Spring 2015 Topic Overview Relationship between the properties of a matrix transformation
More informationLinear Algebra II Lecture 13
Linear Algebra II Lecture 13 Xi Chen 1 1 University of Alberta November 14, 2014 Outline 1 2 If v is an eigenvector of T : V V corresponding to λ, then v is an eigenvector of T m corresponding to λ m since
More informationMAT1302F Mathematical Methods II Lecture 19
MAT302F Mathematical Methods II Lecture 9 Aaron Christie 2 April 205 Eigenvectors, Eigenvalues, and Diagonalization Now that the basic theory of eigenvalues and eigenvectors is in place most importantly
More informationMATH 240 Spring, Chapter 1: Linear Equations and Matrices
MATH 240 Spring, 2006 Chapter Summaries for Kolman / Hill, Elementary Linear Algebra, 8th Ed. Sections 1.1 1.6, 2.1 2.2, 3.2 3.8, 4.3 4.5, 5.1 5.3, 5.5, 6.1 6.5, 7.1 7.2, 7.4 DEFINITIONS Chapter 1: Linear
More informationThe eigenvalues are the roots of the characteristic polynomial, det(a λi). We can compute
A. [ 3. Let A = 5 5 ]. Find all (complex) eigenvalues and eigenvectors of The eigenvalues are the roots of the characteristic polynomial, det(a λi). We can compute 3 λ A λi =, 5 5 λ from which det(a λi)
More informationANALYTICAL MATHEMATICS FOR APPLICATIONS 2018 LECTURE NOTES 3
ANALYTICAL MATHEMATICS FOR APPLICATIONS 2018 LECTURE NOTES 3 ISSUED 24 FEBRUARY 2018 1 Gaussian elimination Let A be an (m n)-matrix Consider the following row operations on A (1) Swap the positions any
More informationMath 1553 Worksheet 5.3, 5.5
Math Worksheet, Answer yes / no / maybe In each case, A is a matrix whose entries are real a) If A is a matrix with characteristic polynomial λ(λ ), then the - eigenspace is -dimensional b) If A is an
More informationMATH SOLUTIONS TO PRACTICE MIDTERM LECTURE 1, SUMMER Given vector spaces V and W, V W is the vector space given by
MATH 110 - SOLUTIONS TO PRACTICE MIDTERM LECTURE 1, SUMMER 2009 GSI: SANTIAGO CAÑEZ 1. Given vector spaces V and W, V W is the vector space given by V W = {(v, w) v V and w W }, with addition and scalar
More informationUnit 5: Matrix diagonalization
Unit 5: Matrix diagonalization Juan Luis Melero and Eduardo Eyras October 2018 1 Contents 1 Matrix diagonalization 3 1.1 Definitions............................. 3 1.1.1 Similar matrix.......................
More informationMath Camp Notes: Linear Algebra II
Math Camp Notes: Linear Algebra II Eigenvalues Let A be a square matrix. An eigenvalue is a number λ which when subtracted from the diagonal elements of the matrix A creates a singular matrix. In other
More informationIMPORTANT DEFINITIONS AND THEOREMS REFERENCE SHEET
IMPORTANT DEFINITIONS AND THEOREMS REFERENCE SHEET This is a (not quite comprehensive) list of definitions and theorems given in Math 1553. Pay particular attention to the ones in red. Study Tip For each
More information