[npl] / trunk / NationalProblemLibrary / ASU-topics / set119MatrixAlgebra / p18.pg Repository: Repository Listing bbplugincoursesdistsnplrochestersystemwww

# View of /trunk/NationalProblemLibrary/ASU-topics/set119MatrixAlgebra/p18.pg

Wed Feb 22 20:38:15 2006 UTC (7 years, 3 months ago) by jjholt
File size: 2066 byte(s)
```Tags as of Feb 22, 2006.
--JH
```

```    1 ## DESCRIPTION
2 ## Matrix Algebra
3 ## ENDDESCRIPTION
4
5 ## KEYWORDS('Algebra' 'Matrix' 'Matrices' 'True' 'False')
6 ## Tagged by tda2d
7
8 ## DBsubject('Algebra')
9 ## DBchapter('Linear Algebra')
10 ## DBsection('Matrix Algebra')
11 ## Date('')
12 ## Author('')
13 ## Institution('ASU')
14 ## TitleText1('')
15 ## EditionText1('')
16 ## AuthorText1('')
17 ## Section1('')
18 ## Problem1('')
19
20 DOCUMENT();
22            "PGchoicemacros.pl",
24
25 );
26 TEXT(beginproblem(), \$BR,\$BBOLD, "True False Problem", \$EBOLD, \$BR,\$BR);
27 # Since this is a true questions, we do not usually wish to tell students which
28 # parts of the matching question have been answered correctly and which are
29 # incorrect.  That is too easy.  To accomplish this we set the following flag to
30 # zero.
32
33 # True false questions are a special case of a "select list"
34 # Make a new select list
35 \$tf = new_select_list();
36 # \$tf now "contains" the select list object.
37 # Insert some  questions and whether or not they are true.
38
39 \$tf -> qa ( # each entry has to end with a comma
40 "If A and B are both square matrices such that AB equals BA equals the identity matrix, then B is the inverse matrix of A.",
41 "T",
42 "If A is a square matrix, then there exists a matrix B such that AB equals the identity matrix.",
43 "F",
44 "If \( AX = B \) represents a system of linear equations and \( A^{-1} \) exists, then the product \( A^{-1}B \) gives the solution to the system.",
45 "T",
46 );   # every statement has to end with a semi-colon.
47
48 # Choose two of the question and answer pairs at random.
49 \$tf ->choose(2);
50
51 # Now print the text using \$ml->print_q for the questions
52 # and \$ml->print_a to print the answers.
53
54 BEGIN_TEXT
55 \$PAR
56
57 Enter T or F depending on whether the statement is true or false.
58 (You must enter T or F -- True and False will not work.)\$BR
59
60 \{ \$tf-> print_q \}
61
62 \$PAR
63
64 END_TEXT
65
66 # Enter the correct answers to be checked against the answers to the students.
67
68 ANS( str_cmp( \$tf->ra_correct_ans )   ) ;
69
70 ENDDOCUMENT();        # This should be the last executable
```