View of /trunk/NationalProblemLibrary/OSU/accelerated_calculus_and_analytic_geometry_ii/hmwk6/prob1.pg

    1 ## DESCRIPTION
    2 ## Conic Sections
    3 ## ENDDESCRIPTION
    4 
    5 ## KEYWORDS('calculus','conic section','parabola','focus','directrix')
    6 ## Tagged by cmd6a 5/30/06
    7 
    8 ## DBsubject('Calculus')
    9 ## DBchapter('Parametric Equations and Polar Coordinates')
   10 ## DBsection('Conic Sections')
   11 ## Date('1/12/2000')
   12 ## Author('Zig Fiedorowicz')
   13 ## Institution('Rochester')
   14 ## TitleText1('Calculus: Early Transcendentals')
   15 ## EditionText1('5')
   16 ## AuthorText1('Stewart')
   17 ## Section1('20')
   18 ## Problem1('')
   19 
   20 ## TitleText2('Calculus: Early Transcendentals')
   21 ## EditionText2('6')
   22 ## AuthorText2('Stewart')
   23 ## Section2('20')
   24 ## Problem2('')
   25 
   26 DOCUMENT();        # This should be the first executable line in the problem.
   27 
   28 loadMacros(
   29 "PG.pl",
   30 "PGbasicmacros.pl",
   31 "PGchoicemacros.pl",
   32 "PGanswermacros.pl",
   33 "PGauxiliaryFunctions.pl"
   34 );
   35 
   36 $showPartialCorrectAnswers = 1;
   37 if (!($studentName =~ /PRACTICE/)) {
   38 $seed = random(1,4,1);
   39 if ($studentName =~ /VINCE VERSION1/) {$seed = 1;}
   40 if ($studentName =~ /VINCE VERSION2/) {$seed = 2;}
   41 if ($studentName =~ /VINCE VERSION3/) {$seed = 3;}
   42 if ($studentName =~ /VINCE VERSION4/) {$seed = 4;}
   43 SRAND($seed);}
   44 
   45 $a = random(2,10,1);
   46 $b = random(3,11,1);
   47 if ($a==$b) {$b++;}
   48 $m = 2*($a+$b);
   49 $c = ($b-$a)/2;
   50 $ans = "$c - y^2/$m";
   51 
   52 TEXT(&beginproblem);
   53 BEGIN_TEXT
   54 Find an equation of the parabola with focus at \((- $a,0)\) and with directrix
   55 \(x = $b\). Express your answer in the form \(x = f(y)\).
   56 $BR
   57 Answer: \(x=\) \{ans_rule(40)\}
   58 
   59 END_TEXT
   60 
   61 &ANS(function_cmp($ans,"y"));
   62 
   63 
   64 ENDDOCUMENT();
   65 
   66 
   67 
   68 
   69 
   70 
   71