How to access an element in XML using namespace (PHP SimpleXMLElement XPath)?

Question

PHP

Good day.
What is the correct way to access elements in XML, if NameSpace is used, with PHP's SimpleXMLElement Xpath?
Fragment

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ns2:export xmlns="http://example.org/oos/types/1" xmlns:ns2="http://example.org/oos/export/1" xmlns:ns3="http://example.org/oos/printform/1">
    <ns2:fcsNotificationEF schemeVersion="6.3">
        <id>123456789</id>

How to correctly make an Xpath request and get access to the id?

Answer 1

php.net/manual/en/simplexmlelement.xpath.php#115957