In default MySQL installation binary files may be located in 

/usr/local/var/

or

/var/lib/mysql/

Their names are ending with -bin.000001, -bin.000002, -bin.000003 etc.

Here is the command that could help you to find location of the logs:

mysql> show variables like '%home%';

As a result, you'll get the list with the locations of the logs.

In order to clear them all run the following command:

mysql> reset master;