Linear Algebra and Its Applications (5th Edition)
Linear Algebra and Its Applications (5th Edition)
5th Edition
ISBN: 9780321982384
Author: David C. Lay, Steven R. Lay, Judi J. McDonald
Publisher: PEARSON
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Chapter 2.4, Problem 13E

Let A = [ B 0 0 C ] , where B and C are square. Show A is invertible if and only if both B and C are invertible.

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Chapter 2 Solutions

Linear Algebra and Its Applications (5th Edition)

Ch. 2.1 - Since vectors in n may be regarded as n 1...Ch. 2.1 - Let A be a 4 4 matrix and let x be a vector in 4....Ch. 2.1 - Suppose A is an m n matrix, all of whose rows are...Ch. 2.1 - In Exercises 1 and 2, compute each matrix sum or...Ch. 2.1 - In Exercises 1 and 2, compute each matrix sum or...Ch. 2.1 - In the rest of this exercise set and in those to...Ch. 2.1 - Compute A 5I3 and (5I3)A, when A=[913876418].Ch. 2.1 - In Exercises 5 and 6, compute die product AB in...Ch. 2.1 - In Exercises 5 and 6, compute die product AB in...Ch. 2.1 - If a matrix A is 5 3 and the product AB is 5 7,...
Ch. 2.1 - How many rows does B have if BC is a 3 4 matrix?Ch. 2.1 - Let A=[2531] and B=[453k]. What value(s) of k, if...Ch. 2.1 - Let A=[2346], B=[8455], and C=[5231]. Verify that...Ch. 2.1 - Let A=[111123145] and D=[200030005]. Compute AD...Ch. 2.1 - Let A=[3612]. Construct a 2 2 matrix B such that...Ch. 2.1 - Let r1,..., rp be vectors in n, and let Q be an m ...Ch. 2.1 - Let U be the 3 2 cost matrix described in Example...Ch. 2.1 - Exercises 15 and 16 concern arbitrary matrices A,...Ch. 2.1 - a. If A and B are 3 3 and B = [b1 b2 b3], then AB...Ch. 2.1 - If A=[1225] and AB=[121693], determine the first...Ch. 2.1 - Suppose the first two columns, b1 and b2, of B are...Ch. 2.1 - Suppose die third column of B is die sum of die...Ch. 2.1 - Suppose the second column of B is all zeros. What...Ch. 2.1 - Suppose the last column of AB is entirely zero but...Ch. 2.1 - Show that if the columns of B are linearly...Ch. 2.1 - Suppose CA = In (the n n identity matrix). Show...Ch. 2.1 - Suppose AD = Im (the m m identity matrix). Show...Ch. 2.1 - Suppose A is an m n matrix and there exist n m...Ch. 2.1 - Suppose A is a 3 n matrix whose columns span 3....Ch. 2.1 - In Exercises 27 and 28, view vectors in n as n 1...Ch. 2.1 - If u and v are in n. how are uTv and vTu related?...Ch. 2.1 - Prove Theorem 2(b) and 2(c). Use the row-column...Ch. 2.1 - Prove Theorem 2(d). [Hint: The (i, j)-entry in...Ch. 2.1 - Show that ImA = A when A is an m n matrix. You...Ch. 2.1 - Show that AIn = A when A is an m n matrix. [Hint:...Ch. 2.1 - Prove Theorem 3(d). [Hint: Consider the jth row of...Ch. 2.1 - Give a formula for (A Bx)T, where x is a vector...Ch. 2.2 - Use determinants to determine which of the...Ch. 2.2 - Find the inverse of the matrix A = [121156545], if...Ch. 2.2 - If A is an invertible matrix, prove that 5A is an...Ch. 2.2 - Find the inverses of the matrices in Exercises 14....Ch. 2.2 - Find the inverses of the matrices in Exercises 14....Ch. 2.2 - Find the inverses of the matrices in Exercises 14....Ch. 2.2 - Find the inverses of the matrices in Exercises 14....Ch. 2.2 - Use the inverse found in Exercise 1 to solve the...Ch. 2.2 - Use the inverse found in Exercise 3 to solve the...Ch. 2.2 - Let A = [12512], b1 = [13], b2 = [15], b3 = [26],...Ch. 2.2 - Use matrix algebra to show that if A is invertible...Ch. 2.2 - In Exercises 9 and 10, mark each statement True or...Ch. 2.2 - a. A product of invertible n n matrices is...Ch. 2.2 - Let A be an invertible n n matrix, and let B be...Ch. 2.2 - Let A be an invertible n n matrix, and let B be...Ch. 2.2 - Suppose AB = AC. where B and C are n p matrices...Ch. 2.2 - Suppose (B C) D = 0, where B and C are m n...Ch. 2.2 - Suppose A, B, and C are invertible n n matrices....Ch. 2.2 - Suppose A and B are n n, B is invertible, and AB...Ch. 2.2 - Solve the equation AB = BC for A, assuming that A,...Ch. 2.2 - Suppose P is invertible and A = PBP1 Solve for B...Ch. 2.2 - If A, B, and C are n n invertible matrices, does...Ch. 2.2 - Suppose A, B, and X are n n matrices with A, X,...Ch. 2.2 - Explain why the columns of an n n; matrix A are...Ch. 2.2 - Explain why the columns of an n n matrix A span n...Ch. 2.2 - Suppose A is n n and die equation Ax = 0 has only...Ch. 2.2 - Suppose A is n n and the equation Ax = b has a...Ch. 2.2 - Exercises 25 and 26 prove Theorem 4 for A =...Ch. 2.2 - Exercises 25 and 26 prove Theorem 4 for A =...Ch. 2.2 - Exercises 27 and 28 prove special cases of the...Ch. 2.2 - Show that if row 3 of A is replaced by row3(A) 4 ...Ch. 2.2 - Find the inverses of the matrices in Exercises...Ch. 2.2 - Find die inverses of the matrices in Exercises...Ch. 2.2 - Find die inverses of the matrices in Exercises...Ch. 2.2 - Find die inverses of the matrices in Exercises...Ch. 2.2 - Use the algorithm from this section to find the...Ch. 2.2 - Repeat the strategy of Exercise 33 to guess the...Ch. 2.2 - Let A = [279256134]. Find the third column of A1...Ch. 2.2 - [M] Let A = [2592754618053715450149]. Find the...Ch. 2.2 - Let A = [121315]. Constuct a 2 3 matrix C (by...Ch. 2.2 - Let A = [11100111]. Construct a 4 2 matrix D...Ch. 2.2 - Let D = [.005.002.001.002.004.002.001.002.005] be...Ch. 2.3 - Determine if A = [234234234] is invertible.Ch. 2.3 - Suppose that for a certain n n matrix A,...Ch. 2.3 - Suppose that A and B are n n matrices and the...Ch. 2.3 - Unless otherwise specified, assume that all...Ch. 2.3 - Unless otherwise specified, assume that all...Ch. 2.3 - Unless otherwise specified, assume that all...Ch. 2.3 - Unless otherwise specified, assume that all...Ch. 2.3 - Unless otherwise specified, assume that all...Ch. 2.3 - Unless otherwise specified, assume that all...Ch. 2.3 - Unless otherwise specified, assume that all...Ch. 2.3 - Unless otherwise specified, assume that all...Ch. 2.3 - Unless otherwise specified, assume that all...Ch. 2.3 - Unless otherwise specified, assume that all...Ch. 2.3 - In Exercises 11 and 12, the matrices are all n n....Ch. 2.3 - In Exercises 11 and 12, the matrices are all n n....Ch. 2.3 - An m n upper triangular matrix is one whose...Ch. 2.3 - An m n lower triangular matrix is one whose...Ch. 2.3 - Can a square matrix with two identical columns be...Ch. 2.3 - Is it possible for a 5 5 matrix to be invertible...Ch. 2.3 - If A is invertible, then the columns of A1 are...Ch. 2.3 - If C is 6 6 and the equation Cx = v is consistent...Ch. 2.3 - If the columns of a 7 7 matrix D are linearly...Ch. 2.3 - If n n matrices E and F have the property that EF...Ch. 2.3 - If the equation Gx = y has more than one solution...Ch. 2.3 - If the equation Hx = c is inconsistent for some c...Ch. 2.3 - If an n n matrix K cannot be row reduced to In....Ch. 2.3 - If L is n n and the equation Lx = 0 has the...Ch. 2.3 - Verify the boxed statement preceding Example 1.Ch. 2.3 - Explain why the columns of A2 span n whenever the...Ch. 2.3 - Show that if AB is invertible, so is A. You cannot...Ch. 2.3 - Show that if AB is invertible, so is B.Ch. 2.3 - If A is an n n matrix and the equation Ax = b has...Ch. 2.3 - If A is an n n matrix and the transformation x ...Ch. 2.3 - Suppose A is an n n matrix with the property that...Ch. 2.3 - Suppose A is an n n matrix with the property that...Ch. 2.3 - In Exercises 33 and 34, T is a linear...Ch. 2.3 - In Exercises 33 and 34, T is a linear...Ch. 2.3 - Let T : n n be an invertible linear...Ch. 2.3 - Let T be a linear transformation that maps n onto...Ch. 2.3 - Suppose T and U are linear transformations from n...Ch. 2.3 - Suppose a linear transformation T : n n has the...Ch. 2.3 - Let T : n n be an invertible linear...Ch. 2.3 - Suppose T and S satisfy the invertibility...Ch. 2.4 - Show that[I0AI] is invertible and find its...Ch. 2.4 - Compute XTX, where X is partitioned as [X1 X2].Ch. 2.4 - In Exercises 19, assume that the matrices are...Ch. 2.4 - In Exercises 19, assume that the matrices are...Ch. 2.4 - In Exercises 19, assume that the matrices are...Ch. 2.4 - In Exercises 19, assume that the matrices are...Ch. 2.4 - In Exercises 58, find formulas for X, Y, and Z in...Ch. 2.4 - In Exercises 58, find formulas for X, Y, and Z in...Ch. 2.4 - In Exercises 58, find formulas for X, Y, and Z in...Ch. 2.4 - In Exercises 58, find formulas for X, Y, and Z in...Ch. 2.4 - Suppose A11 is an invertible matrix. Find matrices...Ch. 2.4 - The inverse of [I00CI0ABI] is [I00ZI0XYI]. Find X,...Ch. 2.4 - In Exercises 11 and 12, mark each statement True...Ch. 2.4 - In Exercises 11 and 12, mark each statement True...Ch. 2.4 - Let A=[B00C], where B and C are square. Show A is...Ch. 2.4 - Show that the block upper triangular matrix A in...Ch. 2.4 - Suppose A11 is invertible. Find X and Y such that...Ch. 2.4 - Suppose the block matrix A on the left side of (7)...Ch. 2.4 - When a deep space probe is launched, corrections...Ch. 2.4 - Let X be an m n data matrix such that XT X is...Ch. 2.4 - In the study of engineering control of physical...Ch. 2.4 - Suppose the transfer function W(S) in Exercise 19...Ch. 2.4 - a. Verify that A2 = I when A=[1031]. b. Use...Ch. 2.4 - Generalize the idea of Exercise 21(a) [not 21(b)]...Ch. 2.4 - Use partitioned matrices to prove by induction...Ch. 2.4 - Use partitioned matrices to prove by induction mat...Ch. 2.4 - Without using row reduction, find the inverse of...Ch. 2.5 - Find an LU factorization of...Ch. 2.5 - In Exercises 16, solve the equation Ax = b by...Ch. 2.5 - In Exercises 16, solve the equation Ax = b by...Ch. 2.5 - In Exercises 16, solve the equation Ax = b by...Ch. 2.5 - In Exercises 16, solve the equation Ax = b by...Ch. 2.5 - In Exercises 16, solve the equation Ax = b by...Ch. 2.5 - In Exercises 16, solve the equation Ax = b by...Ch. 2.5 - Find an LU factorization of the matrices in...Ch. 2.5 - Find an LU factorization of the matrices in...Ch. 2.5 - Find an LU factorization of the matrices in...Ch. 2.5 - Find an LU factorization of the matrices in...Ch. 2.5 - Find an LU factorization of the matrices in...Ch. 2.5 - Find an LU factorization of the matrices in...Ch. 2.5 - Find an LU factorization of the matrices in...Ch. 2.5 - Find an LU factorization of the matrices in...Ch. 2.5 - Find an LU factorization of the matrices in...Ch. 2.5 - Find an LU factorization of the matrices in...Ch. 2.5 - When A is invertible, MATLAB finds A1 by factoring...Ch. 2.5 - Find A1 as in Exercise 17, using A from Exercise...Ch. 2.5 - Let A be a lower triangular n n matrix with...Ch. 2.5 - Let A = LU be an LU factorization. Explain why A...Ch. 2.5 - Suppose A = BC, where B is invertible. Show that...Ch. 2.5 - (Reduced LU Factorization) With A as in the...Ch. 2.5 - (Rank Factorization) Suppose an m n matrix A...Ch. 2.5 - (QR Factorization) Suppose A = QR, where Q and R...Ch. 2.5 - (Singular Value Decomposition) Suppose A = UDVT,...Ch. 2.5 - (Spectral Factorization) Suppose a 3 3 matrix A...Ch. 2.5 - Design two different ladder networks that each...Ch. 2.5 - Show that if three shunt circuits (with...Ch. 2.5 - Prob. 29ECh. 2.5 - Find a different factorization of the A in...Ch. 2.6 - Suppose an economy has two sectors: goods and...Ch. 2.6 - Exercises 14 refer to an economy that is divided...Ch. 2.6 - Exercises 14 refer to an economy that is divided...Ch. 2.6 - Exercises 14 refer to an economy that is divided...Ch. 2.6 - Exercises 14 refer to an economy that is divided...Ch. 2.6 - Consider the production model x = Cx + d for an...Ch. 2.6 - Repeat Exercise 5 with C=[.1.6.5.2], and d=[1811]....Ch. 2.6 - Let C and d be as in Exercise 5. a. Determine the...Ch. 2.6 - Let C be an n n consumption matrix whose column...Ch. 2.6 - Solve the Leontief production equation for an...Ch. 2.6 - The consumption matrix C for the U.S. economy in...Ch. 2.6 - The Leontief production equation, x = Cx + d, is...Ch. 2.6 - Let C be a consumption matrix such that Cm 0 as m...Ch. 2.7 - Rotation of a figure about a point p in 2 is...Ch. 2.7 - What 3 3 matrix will have the same effect on...Ch. 2.7 - Use matrix multiplication to find the image of the...Ch. 2.7 - In Exercises 38, find the 3 3 matrices that...Ch. 2.7 - In Exercises 38, find the 3 3 matrices that...Ch. 2.7 - In Exercises 38, find the 3 3 matrices that...Ch. 2.7 - In Exercises 38, find the 3 3 matrices that...Ch. 2.7 - In Exercises 38, find the 3 3 matrices that...Ch. 2.7 - In Exercises 38, find the 3 3 matrices that...Ch. 2.7 - A 2 200 data matrix D contains the coordinates of...Ch. 2.7 - Consider the following geometric 2D...Ch. 2.7 - Prob. 11ECh. 2.7 - A rotation in 2 usually requires four...Ch. 2.7 - The usual transformations on homogeneous...Ch. 2.7 - Prob. 14ECh. 2.7 - What vector in 3 has homogeneous coordinates...Ch. 2.7 - Are (1. 2, 3, 4) and (10, 20, 30, 40) homogeneous...Ch. 2.7 - Give the 4 4 matrix that rotates points in 3...Ch. 2.7 - Give the 4 4 matrix that rotates points in 3...Ch. 2.7 - Let S be the triangle with vertices (4.2, 1.2,4),...Ch. 2.7 - Let S be the triangle with vertices (9,3,5),...Ch. 2.7 - [M] The actual color a viewer sees on a screen is...Ch. 2.7 - [M] The signal broadcast by commercial television...Ch. 2.8 - Let A=[115207353] and u=[732] Is u in Nul A? Is u...Ch. 2.8 - Given A=[010001000], find a vector in Nul A and a...Ch. 2.8 - Suppose an n n matrix A is invertible. What can...Ch. 2.8 - Exercises 14 display sets in 2. Assume the sets...Ch. 2.8 - Exercises 14 display sets in 2. Assume the sets...Ch. 2.8 - Exercises 14 display sets in 2. Assume the sets...Ch. 2.8 - Exercises 1-4 display sets in 2. Assume the sets...Ch. 2.8 - Let v1 = [235], v2 = [458], and w = [829]....Ch. 2.8 - Let v1 = [1243], v2 = [4797], v3 = [5865], and u =...Ch. 2.8 - Let v1 = [286], v2 = [387], v3 = [467], p =...Ch. 2.8 - Let v1 = [306], v2 = [223], v3 = [063], and p =...Ch. 2.8 - With A and p as in Exercise 7, determine if p is...Ch. 2.8 - With u = (2, 3, 1) and A as in Exercise 8,...Ch. 2.8 - In Exercises 11 and 12. give integers p and q such...Ch. 2.8 - In Exercises 11 and 12. give integers p and q such...Ch. 2.8 - For A as in Exercise 11, find a nonzero vector in...Ch. 2.8 - For A as in Exercise 12, find a nonzero vector in...Ch. 2.8 - Determine which sets in Exercises 15-20 are bases...Ch. 2.8 - Determine which sets in Exercises 15-20 are bases...Ch. 2.8 - Determine which sets in Exercises 15-20 are bases...Ch. 2.8 - Determine which sets in Exercises 15-20 are bases...Ch. 2.8 - Determine which sets in Exercises 15-20 are bases...Ch. 2.8 - Determine which sets in Exercises 15-20 are bases...Ch. 2.8 - In Exercises 21 and 22, mark each statement True...Ch. 2.8 - a. A subset H of n is a subspace if the zero...Ch. 2.8 - Exercises 23-26 display a matrix A and an echelon...Ch. 2.8 - Exercises 23-26 display a matrix A and an echelon...Ch. 2.8 - Exercises 23-26 display a matrix A and an echelon...Ch. 2.8 - Exercises 23-26 display a matrix A and an echelon...Ch. 2.8 - Construct a nonzero 3 3 matrix A and a nonzero...Ch. 2.8 - Construct a nonzero 3 3 matrix A and a vector b...Ch. 2.8 - Construct a nonzero 3 3 matrix A and a nonzero...Ch. 2.8 - Suppose the columns of a matrix A = [a1 ap] are...Ch. 2.8 - In Exercises 31-36, respond as comprehensively as...Ch. 2.8 - In Exercises 31-36. respond as comprehensively as...Ch. 2.8 - In Exercises 31-36, respond as comprehensively as...Ch. 2.8 - In Exercises 31-36, respond as comprehensively as...Ch. 2.8 - In Exercises 31-36, respond as comprehensively as...Ch. 2.8 - In Exercises 31-36, respond as comprehensively as...Ch. 2.8 - [M] In Exercises 37 and 38, construct bases for...Ch. 2.8 - [M] In Exercises 37 and 38, construct bases for...Ch. 2.9 - Determine the dimension of the subspace H of 3...Ch. 2.9 - Prob. 2PPCh. 2.9 - Could 3 possibly contain a four-dimensional...Ch. 2.9 - In Exercises 1 and 2, find the vector x determined...Ch. 2.9 - In Exercises 1 and 2, find the vector x determined...Ch. 2.9 - In Exercises 3-6, the vector s is in a subspace H...Ch. 2.9 - In Exercises 1 and 2, find the vector x determined...Ch. 2.9 - In Exercises 3-6, the vector x is in a subspace H...Ch. 2.9 - In Exercises 3-6, the vector x is in a subspace H...Ch. 2.9 - Let b1 = [30], b2 = [12], w = [72], x = [41], and...Ch. 2.9 - Let b1 = [02], b2 = [21], x = [23], y = [24], z =...Ch. 2.9 - Exercises 9-12 display a matrix A and an echelon...Ch. 2.9 - Exercises 9-12 display a matrix A and an echelon...Ch. 2.9 - Exercises 9-12 display a matrix A and an echelon...Ch. 2.9 - Exercises 9-12 display a matrix A and an echelon...Ch. 2.9 - In Exercises 13 and 14, find a basis for the...Ch. 2.9 - In Exercises 13 and 14, find a basis for the...Ch. 2.9 - Suppose a 3 5 matrix A has three pivot columns....Ch. 2.9 - Suppose a 4 7 matrix A has three pivot columns....Ch. 2.9 - In Exercises 17 and 18, mark each statement True...Ch. 2.9 - In Exercises 17 and 18, mark each statement True...Ch. 2.9 - If the subspace of all solutions of Ax = 0 has a...Ch. 2.9 - What is the rank of a 4 5 matrix whose null space...Ch. 2.9 - If the tank of a 7 6 matrix A is 4, what is the...Ch. 2.9 - Show that a set of vectors {v1, v2, , v5} in n is...Ch. 2.9 - If possible, construct a 3 4 matrix A such that...Ch. 2.9 - Constructa4 3 matrix with tank 1.Ch. 2.9 - Let A be an n p matrix whose column space is...Ch. 2.9 - Suppose columns 1, 3, 5, and 6 of a matrix A are...Ch. 2.9 - Suppose vectors b1, bp span a subspace W, and let...Ch. 2.9 - Use Exercise 27 to show that if A and B are bases...Ch. 2.9 - Prob. 29ECh. 2.9 - [M] Let H = Span {v1, v2, v3} and B= {v1, v2,...Ch. 2 - Assume that the matrices mentioned in the...Ch. 2 - Find the matrix C whose inverse is C1 = [4567].Ch. 2 - Show that A = [000100010]. Show that A3 = 0. Use...Ch. 2 - Suppose An = 0 for some n 1. Find an inverse for...Ch. 2 - Suppose an n n matrix A satisfies the equation A2...Ch. 2 - Prob. 6SECh. 2 - Let A = [1382411125] and B = [351534]. Compute A1B...Ch. 2 - Find a matrix A such that the transformation x Ax...Ch. 2 - Suppose AB =[5423] and B = [7321]. Find A.Ch. 2 - Suppose A is invertible. Explain why ATA is also...Ch. 2 - Let x1, , xn, be fixed numbers. The matrix below,...Ch. 2 - Prob. 12SECh. 2 - Given u in n with uTu = 1, Let P = uuT (an outer...Ch. 2 - Prob. 14SECh. 2 - Prob. 15SECh. 2 - Let A be an n n singular matrix Describe how to...Ch. 2 - Let A be a 6 4 matrix and B a 4 6 matrix. Show...Ch. 2 - Suppose A is a 5 3 matrix and mere exists a 3 5...Ch. 2 - Prob. 19SECh. 2 - [M] Let An be the n n matrix with 0s on the main...

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