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Get Full Access to Linear Algebra With Applications - 9 Edition - Chapter 3 - Problem 2
Get Full Access to Linear Algebra With Applications - 9 Edition - Chapter 3 - Problem 2

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# (Rank-Deficient Matrices) In this exercise we consider how to use MATLAB to generate ISBN: 9780321962218 437

## Solution for problem 2 Chapter 3

Linear Algebra with Applications | 9th Edition

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Problem 2

(Rank-Deficient Matrices) In this exercise we consider how to use MATLAB to generate matrices with specified ranks. (a) In general, if A is an m n matrix with rank r, then r min(m, n). Why? Explain. If the entries of A are random numbers, we would expect that r = min(m, n). Why? Explain. Check this out by generating random 6 6, 8 6, and 5 8 matrices and using the MATLAB command rank to compute their ranks. Whenever the rank of an mn matrix equals min(m, n), we say that the matrix has full rank. Otherwise, we say that the matrix is rank deficient. (b) MATLABs rand and round commands can be used to generate random m n matrices with integer entries in a given range [a, b]. This can be done with a command of the form A = round((b a) rand(m, n)) + a For example, the command A = round(4 rand(6, 8)) + 3 will generate a 6 8 matrix whose entries are random integers in the range from 3 to 7. Using the range [1, 10], create random integer 10 7, 8 12, and 10 15 matrices and in each case check the rank of the matrix. Do these integer matrices all have full rank? (c) Suppose that we want to use MATLAB to generate matrices with less than full rank. It is easy to generate matrices of rank 1. If x and y are nonzero vectors in Rm and Rn, respectively, then A = xyT will be an m n matrix with rank 1. Why? Explain. Verify this in MATLAB by setting x = round(9 rand(8, 1)) + 1, y = round(9 rand(6, 1)) + 1 and using these vectors to construct an 86 matrix A. Check the rank of A with the MATLAB command rank. (d) In general, rank(AB) min(rank(A), rank(B)) (1) (See Exercise 28 in Section 3.6.) If A and B are noninteger random matrices, the relation (1) should be an equality. Generate an 8 6 matrix A by setting X = rand(8, 2), Y = rand(6, 2), A = X Y What would you expect the rank of A to be? Explain. Test the rank of A with MATLAB. (e) Use MATLAB to generate matrices A, B, and C such that (i) A is 8 8 with rank 3. (ii) B is 6 9 with rank 4. (iii) C is 10 7 with rank 5.

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L33 - 5 Fundamental Theorem of Calculus, Part II: If f is continuous on [a,b], then ▯ b f(x)dx = a ▯ where F is any antiderivative of f. (That is, F (x)= )

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##### ISBN: 9780321962218

This full solution covers the following key subjects: . This expansive textbook survival guide covers 47 chapters, and 935 solutions. Since the solution to 2 from 3 chapter was answered, more than 237 students have viewed the full step-by-step answer. The answer to “(Rank-Deficient Matrices) In this exercise we consider how to use MATLAB to generate matrices with specified ranks. (a) In general, if A is an m n matrix with rank r, then r min(m, n). Why? Explain. If the entries of A are random numbers, we would expect that r = min(m, n). Why? Explain. Check this out by generating random 6 6, 8 6, and 5 8 matrices and using the MATLAB command rank to compute their ranks. Whenever the rank of an mn matrix equals min(m, n), we say that the matrix has full rank. Otherwise, we say that the matrix is rank deficient. (b) MATLABs rand and round commands can be used to generate random m n matrices with integer entries in a given range [a, b]. This can be done with a command of the form A = round((b a) rand(m, n)) + a For example, the command A = round(4 rand(6, 8)) + 3 will generate a 6 8 matrix whose entries are random integers in the range from 3 to 7. Using the range [1, 10], create random integer 10 7, 8 12, and 10 15 matrices and in each case check the rank of the matrix. Do these integer matrices all have full rank? (c) Suppose that we want to use MATLAB to generate matrices with less than full rank. It is easy to generate matrices of rank 1. If x and y are nonzero vectors in Rm and Rn, respectively, then A = xyT will be an m n matrix with rank 1. Why? Explain. Verify this in MATLAB by setting x = round(9 rand(8, 1)) + 1, y = round(9 rand(6, 1)) + 1 and using these vectors to construct an 86 matrix A. Check the rank of A with the MATLAB command rank. (d) In general, rank(AB) min(rank(A), rank(B)) (1) (See Exercise 28 in Section 3.6.) If A and B are noninteger random matrices, the relation (1) should be an equality. Generate an 8 6 matrix A by setting X = rand(8, 2), Y = rand(6, 2), A = X Y What would you expect the rank of A to be? Explain. Test the rank of A with MATLAB. (e) Use MATLAB to generate matrices A, B, and C such that (i) A is 8 8 with rank 3. (ii) B is 6 9 with rank 4. (iii) C is 10 7 with rank 5.” is broken down into a number of easy to follow steps, and 404 words. Linear Algebra with Applications was written by and is associated to the ISBN: 9780321962218. The full step-by-step solution to problem: 2 from chapter: 3 was answered by , our top Math solution expert on 03/15/18, 05:26PM. This textbook survival guide was created for the textbook: Linear Algebra with Applications, edition: 9.

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