CHAPTER 16 PRACTICE TEST

As a study aid, we have included complete solutions for each Practice Test problem at the end of this book.

  1. For matrices A and B, find A − 2B . 

    A =  [ 3 − 1420 − 2 ] B =  [ 145 − 1 − 23 ] 
  2. Evaluate the literal symbols.

     [ 2xx − yzx + z2yy + z ]  =  [ 6 − 24abc ] 
  3. For matrices C and D, find CD and DC, if possible.

    C =  [ 1042 − 21 − 132 ] D =  [ 2 − 24 − 561 ] 
  4. Determine whether or not B = A − 1 . 

    A =  [ 2 − 51 − 2 ] B =  [  − 25 − 12 ] 
  5. For matrix C of Problem 3, find C − 1 . 

  6. Solve by using the inverse of the coefficient matrix.

    2x − 3y = 11x + 2y = 2
  7. Solve the system of equations in Problem 6 by Gaussian elimination.

  8. Evaluate the following determinant by expansion by minors.

     | 2 − 4 − 3 − 3625 − 15 | 
  9. Solve the following system of equations by using the inverse of the coefficient matrix. Use a calculator to perform the necessary matrix operations and display the result and check. Write down the display shown in the window with the solutions.

    7x − 2y + z = 62x + 3y − 4z = 64x − 5y + 2z = 10
  10. Fifty shares of stock A and 30 shares of stock B cost $2600. Thirty shares of stock A and 40 shares of stock B cost $2000. What is the price per share of each stock? Solve by setting up the appropriate equations and then using the inverse of the coefficient matrix.

..................Content has been hidden....................

You can't read the all page of ebook, please click here login for view all page.
Reset
3.133.141.6