use Math::Calculus::NewtonRaphson;

use strict;
use warnings;

my $exp = Math::Calculus::NewtonRaphson->new();
$exp->addVariable('x'); # our variable in the equations
$exp->setExpression('x+3*x-x^2');
if( $exp->getError() ){ print "got error, ".$exp->getError()."\n"; exit(1) }
my $result = $exp->newtonRaphson('x', 0);
print "result: ".$result."\n";