Instead of telling you where it most likely is, it may be best to show how you can easily discover these (and many other) settings as they may be in various locations. First, you would need to create a file in your web directory root, something like
/var/www/html/info.php. In that file you would need to place the following lines of code:
Now if you visit your site (http://example.com/info.php) you'll see all you php build and configuration information. You can run a find in your browser for Configuration File and you will see the path for the php.ini file. If you search for and error_log, you'll see the location of the php error log.
Platform Support Specialist