** Using WeBWorK **

It might be possible to overwrite the functions for sine and cosine as Davide did for handling square root simplifications (just do this for sine and cosine instead of sqrt):

# code essentially from Davide Cervone 4/25/10

###########################

#

# Subclass the numeric functions

#

package my::Function::numeric;

our @ISA = ('Parser::Function::numeric');

#

# Override sqrt() to return a special value (usually 1) when evaluated

# effectively eliminating it from the product.

#

sub sqrt {

my $self = shift;

my $value = $self->context->flag("setSqrt");

return $value+2 if $value && $_[0] == 1; # force sqrt(1) to be incorrect

return $value if $value;

return $self->SUPER::sqrt(@_);

}

#

# end of subclass

#

package main;

Context("Numeric")->variables->are(

x => ["Real", limits => [0,2]], # only needed if x is used in the square roots

);

#

# make sqrt() use our subclass

#

Context()->functions->set(sqrt=>{class=>'my::Function::numeric'});

Context()->flags->set(reduceConstantFunctions=>0);

#

#

# Don't allow fractional powers (avoids 1/2 power)

# [Could subclass exponentiation to handle that as well]

#

LimitedPowers::OnlyPositiveIntegers();

$reducedSqrt = sub {

my ($correct,$student,$ans) = @_;

return 0 if $ans->{isPreview} || $correct != $student;

#

# Get parsed formula for student and correct answers

#

$student = $ans->{student_formula};

$correct = $correct->{original_formula} if defined $correct->{original_formula};

#

# check if equal when sqrt's are replaced by 1

#

Context()->flags->set(setSqrt => 1);

delete $correct->{test_values}, $student->{test_values};

my $OK = ($correct == $student);

Context()->flags->set(setSqrt => 0);

#

Value::Error("Check to see if your answer is simplified.") unless $OK;

return $OK;

};

ANS($ans1->cmp(checker => $reducedSqrt,formatStudentAnswer=>"reduced"));