Question

is there any function in PHP which would get the cotangent and arccotangent of my number?

Thanks

Answer 1

Take a look at the tan function in the PHP manual for the cotangent, notably the comment here for cotangents

<?php
//FOR PHP 4
function cot($rad)
{
    return tan(M_PI_2 - rad2deg($rad));
}

//FOR PHP 3
function cot($rad)
{
    return tan(M_PI/2 - rad2deg($rad));
}
?>

See here for #2