function fibonacci_binet ($n
{
$phi = (1 + sqrt(5)) / 2;
$u = (pow$phi, $n) - pow(1 - $phi, $n)) / sqrt(5);
return $u
}
function fibonacci_binet ($n
{
$phi = (1 + sqrt(5)) / 2;
$u = (pow$phi, $n) - pow(1 - $phi, $n)) / sqrt(5);
return $u
}