** Using WeBWorK **

DOCUMENT();

loadMacros(

"PGstandard.pl", #loads four macros you loaded

"MathObjects.pl", #almost always best practice

"contextIntegerFunctions.pl",
"PGML.pl", #my preference; easier for
#future users to work with
"PGcourse.pl", #allow yourself and future
#users to make course-wide
#customizations by editing this

);

TEXT(beginproblem()); #somewhere I heard it's better
#to cease using & and use ()
#instead; can't recall why

$a = non_zero_random(-6,6,2);

$b = non_zero_random(-6,6,2);

$c = random(3,7);

$d = random(10,15);

$e = $c+$d;

Context("IntegerFunctions");

$ans = Real("($a)^($c) ($b)^($d) C($e,$d)");
#makes $ans a MathObject Real, which among other
#things will enable special feedback messages to
#certain incorrect answers automatically;
#by using quotes, you pass a string instead of a
#perl real, and you can use ^ instead of **;
#the parens are needed in the bases, probably
#extraneous for the exponents

Context()->variables->add(y=>'Real');
$f=Formula("($a x + $b y)^($e)")->reduce;
#in case $a or $b is -1, 0, or 1; which is not #possible with your randomization, but this
#is generally helpful
$term=Formula("x^($c)y^($d)")->reduce;

#PGML feels cleaner to me and easier for a future
#person to work with; also you get the answer
#evaluation right next to the answer blank

BEGIN_PGML

What is the coefficient of [`[$term]`] in the expansion of [`[$f]`]?

[_____________]{$ans}

END_PGML

ENDDOCUMENT();