1. Given [A] = then [A] is  a ______________  matrix.

diagonal

identity

lower triangular

upper triangular

2. A square matrix [A] is lower triangular if

3. Given  ,  then if [C] = [A] [B], then c₃₁= _____________________

-58.2

-37.6

219.4

259.4

4. The following system of equations has ____________ solution(s).

        x + y = 2

        6x+6y =12

infinite

no

two

unique

5. Consider there are only two computer companies in a country.  The companies are named Dude and Imac.  Each year, company Dude keeps 1/5^th of its customers, while the rest switch to Imac.  Each year, Imac keeps 1/3^rd of its customers, while the rest switch to Dude.  If in 2003, Dude had 1/6^th of the market and Imac had 5/6^th of the market, what will be share of Dude computers when the market becomes stable?

37/90

5/11

6/11

53/90

6. Three kids - Jim, Corey and David receive an inheritance of $2,253,453.  The money is put in three trusts but is not divided equally to begin with.  Corey's trust is three times that of David's because Corey made an A in Dr. Kaw’s class.  Each trust is put in an interest generating investment.  The three trusts of Jim, Corey and David pays an interest of 6%, 8%, 11%, respectively.  The total interest of all the three trusts combined at the end of the first year is $190,740.57.  The equations to find the trust money of Jim (J), Corey (C) and David (D) in a matrix form is 

Multiple choice questions on other topics

Copyrights: University of South Florida, 4202 E Fowler Ave, Tampa, FL 33620-5350. All Rights Reserved. Questions, suggestions or comments, contact kaw@eng.usf.edu  This material is based upon work supported by the National Science Foundation under Grant# 0126793, 0341468 and 0717624.  Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.  Other sponsors include Maple, MathCAD, USF, FAMU and MSOE.