1.   Does the inverse of exist? If it does not exist, explain why not.
    A. No; the determinant equals 0.
    B. No; the elements of the principal diagonal are not 1.
    C. No; the matrix is not square.
    D. Yes
    Hint

  2.   Determine whether the pair of matrices are inverses.
    A. no, because fractions cannot be a part of an inverse
    B. no, because A · B I
    C. yes, because each entry in the second matrix is the reciprocal of its corresponding entry in the first matrix
    D. yes, because A · B = I
    Hint

  3.   Determine whether the pair of matrices are inverses.
    A. no, because fractions cannot be a part of an inverse B. yes, because each entry in the second matrix is the reciprocal of its corresponding entry in the first matrix.
    C. yes, because A · B = I. D. no, because A · B I
    Hint

  4.   What is the 4 × 4 identity matrix?
    A. B.
    C. D.
    Hint

  5.   Find the inverse of if it exists.
    A. B.
    C. does not exist, since adbc = 0 D.
    Hint



Glencoe
The McGraw-Hill Companies