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

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

Sat Jan 14 02:13:08 2006 UTC (7 years, 4 months ago) by jj
File size: 1712 byte(s)
```New problems for the library.
```

```    1 DOCUMENT();
3            "PGchoicemacros.pl",
5
6 );
7 TEXT(beginproblem(), \$BR,\$BBOLD, "True False Problem", \$EBOLD, \$BR,\$BR);
8 # Since this is a true questions, we do not usually wish to tell students which
9 # parts of the matching question have been answered correctly and which are
10 # incorrect.  That is too easy.  To accomplish this we set the following flag to
11 # zero.
13
14 # True false questions are a special case of a "select list"
15 # Make a new select list
16 \$tf = new_select_list();
17 # \$tf now "contains" the select list object.
18 # Insert some  questions and whether or not they are true.
19
20 \$tf -> qa ( # each entry has to end with a comma
21 "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.",
22 "T",
23 "If A is a square matrix, then there exists a matrix B such that AB equals the identity matrix.",
24 "F",
25 "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.",
26 "T",
27 );   # every statement has to end with a semi-colon.
28
29 # Choose two of the question and answer pairs at random.
30 \$tf ->choose(2);
31
32 # Now print the text using \$ml->print_q for the questions
33 # and \$ml->print_a to print the answers.
34
35 BEGIN_TEXT
36 \$PAR
37
38 Enter T or F depending on whether the statement is true or false.
39 (You must enter T or F -- True and False will not work.)\$BR
40
41 \{ \$tf-> print_q \}
42
43 \$PAR
44
45 END_TEXT
46
47 # Enter the correct answers to be checked against the answers to the students.
48
49 ANS( str_cmp( \$tf->ra_correct_ans )   ) ;
50
51 ENDDOCUMENT();        # This should be the last executable
```