SampleProblem4
A PGML WeBWorK Sample Problem
This sample problem illustrates the basics of how to use PGML commands to layout a question.
As usual a standard WeBWorK PG file has five sections:
 A tagging and description section, that describes the problem for future users and authors,
 An initialization section, that loads required macros for the problem,
 A problem setup section that sets variables specific to the problem,
 A text section, that gives the text that is shown to the student, and
 OPTIONAL An answer , that specifies how the answer(s) to the problem is(are) marked for correctness, and gives a solution that may be shown to the student after the problem set is complete. As you will see this section can be used but are not necessary when using PGML commands.
 A solution section
The sample file attached to this page shows this; below the file is shown to the left, with a second column on its right that explains the different parts of the problem that are indicated above.
PG problem file  Explanation 

# DESCRIPTION # A simple sample problem that asks students to # differentiate a trigonometric function. # WeBWorK problem written by Gavin LaRose # <glarose(at)umich(dot)edu> # and modified by Mike Gage gage(at)math(dot)rochester(dot)edu # ENDDESCRIPTION ## DBsubject('WeBWorK') ## DBchapter('Demos') ## DBsection('Problem') ## KEYWORDS('') ## TitleText1('') ## EditionText1('') ## AuthorText1('') ## Section1('') ## Problem1('') ## Author('Gavin LaRose') ## Institution('UMich') 
This is the tagging and description section of the problem. Note that any line that begins with a "#" character is a comment for other authors who read the problem, and is not interpreted by !WeBWorK. The description is provided to give a quick summary of the problem so that someone reading it later knows what it does without having to read through all of the problem code. All of the tagging information exists to allow the problem to be easily indexed. Because this is a sample problem there isn't a textbook per se, and we've used some default tagging values. There is an online list of current chapter and section names and a similar list of keywords. The list of keywords should be comma separated and quoted (e.g., KEYWORDS('calculus','derivatives')). 
DOCUMENT(); loadMacros( "PGstandard.pl", "PGML.pl", "MathObjects.pl", "PGcourse.pl", ); 
This is the initialization section of the problem. The first executed line of the problem must be the
The

# make sure we're in the context we want Context("Numeric"); $showPartialCorrectAnswers = 1; $f = Formula("cos^2(x)+sin^2(x)"); 
This is the problem setup section of the problem.
The bulk of the setup section defines variables that we use in the rest of the problem. All scalar variables are prefaced with a dollar sign: thus 
TEXT(beginproblem()); #TEXT(PGML::Format2(<<'END_PGML')); BEGIN_PGML The number twelve is [_______]{12} Type the formula [`1+\frac{x}{2}`] [__________]{"1+x/2"} Twelve is [______]{Real(12)} 2 mod 10 is [______]{Real(2)>with(period=>10)} [`[$f]`] is equal to [_______]{Real(1)} Twelve is [______]{num_cmp(12)} The number 12 is [____]{answer=>12,width=>10} END_PGML 
This is the text section of the problem. The
Answer blanks are indicated by

ANS( $trigDeriv>cmp() ); Context()>texStrings; SOLUTION(EV3(<<'END_SOLUTION')); $PAR SOLUTION $PAR We find the derivative to this using the chain rule. The inside function is \($a x\), so that its derivative is \($a\), and the outside function is \(\sin(x)\), which has derivative \(\cos(x)\). Thus the solution is \[ \frac{d}{dx} $trigFunc = $trigDeriv. \] END_SOLUTION Context()>normalStrings; ENDDOCUMENT(); 
This is the answer and solution section of the problem. The problem answer is set by the Then, we explain the solution to the student. This solution will show up when the student clicks the "show solution" checkbox after they've finished the problem set.
The 