(9) True of False: For all (n xn) matrices A and B, dim(ker(AB)) > dim(ker(B)). (That...
3.23 True or false. justify your answer 190 LINEAR TRANSFORMATIONS 3.22 Let A be a 4 x 3 matrix and B a 3 x 4 matrix. Then AB cannot be in 3.23 Suppose that A is an invertible matrix and B is any matrix for which BA i 3.24 Suppose that A is an invertible matrix and B is any matrix for which AB is 3.25 Suppose that A and B are nxn matrices such that AB is invertible. Then...
11. Prove one of the following: a. Let A and B be square matrices. If det(AB) + 0, explain why B is invertible. b. Suppose A is an nxn matrix and the equation Ax = 0 has a nontrivial solution. Explain why Rank A<n.
P.2.16 Let V= span {AB-BA : A, B E Mn. (a) Show that the function tr : M,,-> C is a linear transformation. (b) Use the dimension theorem to prove that dim ker tr = n2-1. (c) Prove that dim V = n2-1. (d) Let Eij=eie), every entry of which is zero except for a 1 in the (i, j) position. Show that k,-OikEil for l i, j, k, n. (e) Find a basis for V. Hint: Work out the...
5 points 1. True of False: a. if A is an n x1 matrix and B is a 1 xn matrix, then AB is an n xn matrix. b. if A is an n x1 matrix and B is a 1 x n matrix, then BA is not defined. 20 points 2. Use the Invertible Matrix Theorem to determine which of the matrices below are invert- ible. Use as few calculations as possible. Justify your answers. [34 01 4 5...
Determine if the statements are true or false. 1. If A and B are nxn matrices and if A is invertible, then ABA-1 = B. ? A 2. If A and B are real symmetric matrices of size nxn, then (AB)? = BA 3. If A is row equivalent to B, then the systems Ax = 0 and Bx = 0 have the same solution. ? A 4. If, for some matrix A and some vectors x and b we...
Let A and B be n by n matrices and suppose that tr(AB)=0. Which of the following statements can you infer about A and B? Select one: a. At least one of the matrices A and B must equal the zero matrix O b. A must equal the zero matrix O c. B must equal the zero matrix O d. Both A and B must equal the zero matrix e. AB must equal the zero matrix O f. None of...
19. Suppose A and B are n xn matrices. a. Suppose that both A and B are diagonalizable and that they have the same eigen- vectors. Prove that AB = BA. b. Suppose A has n distinct eigenvalues and AB = BA. Prove that every eigen vector of A is also an eigen vector of B. Conclude that B is diagonalizable. (Query: Need every eigenvector of B be an eigenvector of A?)
Vetermine whether each statement is true or false. If a statement is true, give a reason or ote an appropriate statement from the text. If a statement is false provide an example that shows that the statement is not true in all cases or cite an appropriate statement from the text. (a) The determinant of the sum of two matrices equals the sum of the determinants of the matrices. o, consider the following matrica ( 8 ) and (3) O...
Problem 1. (15 points) Answer the following true or false (ao proof or argurment needed). (a). True or False: solutions. There exists a system of linear equations which has exactly two TrUR (b). True or False: most one IfA is an m x n matrix with null(A) = 0 then AE = 6 has at solution. yhjL (c). True or False: If A and B are invertible nxn matrices then AB is invertible and (AB)-1 = A-B- Fals R. Then...