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(1 point) Determine if the statements are true or false. 1. Any four vectors in

ID: 3116804 • Letter: #

Question

(1 point) Determine if the statements are true or false. 1. Any four vectors in R3 are linearly dependent?' 2. Any four vectors in R3 span R3 3. The rank of a matrix is equal to the number of pivots in its RREF.' ? 4(vi , v, , . . . ,%) is a basis for span(vi,v,, ,v,) . 5. If v is an eigenvector of a matrix A, then v is an eigenvector of AcI for all scalars c. (Here I denotes the identity matrix of the same dimension as A.)' 6. An n x n matrix A is diagonalizable if and only if it has n distinct eigenvalues.' 7. Let W be a subspace of R". If p is the projection of b onto W, then b peW?

Explanation / Answer

1.The statement is True. The dimension of R3 is 3. Therefore, any set of 4 vectors in R3 is linearly dependent.

2.The statement is False. The set { (1,0,0),(0,1,0),(1,1,0), (1,3,0)} does not span R3.

3. The statement is True. It is one of the definitions of the rank of a matrix.

4. The statement is False. The set {v1,v2,…,vn} will be a basis for span(v1,v2,…,vn)provided the vectors v1,v2,…,vn are linearly independent and not otherwise.

5. The statement is True. If v is an eigenvector of A associated with the eigenvalue and if c is a scalar, then v is an eigenvector of A+cI with corresponding eigenvalue + c.

6. The statement is False. A nxn matrix A is diagonalizable if and only if it has n distinct and linearly independent eigenvectors. A always has n eigenvalues. Some of these may have algebraic multiplicity more than 1. This, however, may not affect the diagonalizability of A.

7. The statement is True. The vector b p is the error vector, which is perpendicular to W . Hence b-p W .