View of /trunk/NationalProblemLibrary/ASU-topics/setContinuity/4-1-37.pg

    1 ## DESCRIPTION
    2 ## Calculus
    3 ## ENDDESCRIPTION
    4 
    5 ## KEYWORDS('calculus', 'continuity')
    6 ## Tagged by YL
    7 
    8 ## DBsubject('Calculus')
    9 ## DBchapter('Single Variable')
   10 ## DBsection('Continuity')
   11 ## Date('')
   12 ## Author('')
   13 ## Institution('ASU')
   14 ## TitleText1('Calculus')
   15 ## EditionText1('5e')
   16 ## AuthorText1('Stewart')
   17 ## Section1('')
   18 ## Problem1('')
   19 
   20 DOCUMENT();        # This should be the first executable line in the problem.
   21 
   22 loadMacros("PG.pl",
   23            "PGbasicmacros.pl",
   24            "PGchoicemacros.pl",
   25            "PGanswermacros.pl",
   26            "PGauxiliaryFunctions.pl",
   27     "extraAnswerEvaluators.pl");
   28 
   29 $a = random(2,8,1);
   30 $b = random(1,9,1);
   31 
   32 TEXT(beginproblem());
   33 
   34 $showPartialCorrectAnswers = 1;
   35 
   36 
   37 
   38 TEXT(EV3(<<'EOT'));
   39 Use interval notation to indicate the set of solutions
   40 to the inequality
   41 \[ \frac{x^2 + $a x}{x - $b} > 0. \]
   42 $PAR
   43 $PAR
   44 $BBOLD NOTE: $EBOLD
   45 When using interval notation in WeBWorK, remember
   46 that:
   47 $BR $SPACE $SPACE $SPACE $SPACE You use 'I' for \(\infty\) and '-I' for \(-\infty\).
   48 $BR $SPACE $SPACE $SPACE $SPACE And use 'U' for the union symbol.
   49 
   50 $PAR
   51 Solution:
   52 $BR
   53 \{ans_rule(25)\}
   54 $PAR
   55 $PAR
   56 EOT
   57 
   58 @answers = "(-$a,0)U($b,I)";
   59 
   60 
   61 ANS( interval_cmp(@answers) );
   62 
   63 ENDDOCUMENT();        # This should be the last executable line in the problem.