$ cd /usr/local/mysql/bin
$ ./mysqladmin -u root password 'password'

Welcome to the MySQL monitor.  Commands end with ; or g.
Your MySQL connection id is 224
Server version: 5.5.13 MySQL Community Server (GPL)

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owners.

Type 'help;' or 'h' for help. Type 'c' to clear the current input statement.

mysql>

$ mysql -u root
mysql> USE mysql;
mysql> UPDATE user SET password=PASSWORD("NEWPASSWORD") WHERE User='root';
mysql> FLUSH PRIVILEGES;
mysql> quit

mysql> UPDATE user SET authentication_string=PASSWORD("NEWPASSWORD") WHERE User='root';

/usr/local/mysql/bin/mysqladmin -u root password NEW_PASSWORD_HERE

cd /usr/local/mysql/bin/
./mysql -u root -p
> Enter password: [type old password invisibly]

use mysql;
update user set password=PASSWORD("NEW_PASSWORD_HERE") where User='root';
flush privileges;
quit

1. sudo /usr/local/mysql/support-files/mysql.server stop
2) sudo /usr/local/mysql/support-files/mysql.server start --skip-grant-tables
3) /usr/local/mysql/support-files/mysql
4) mysql> FLUSH PRIVILEGES;
5) mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'MyNewPass';
6) Ctrl + z
7) sudo /usr/local/mysql/support-files/mysql.server start
8) /usr/local/mysql/support-files/mysql -u root -p
9) enter the new password i.e MyNewPass

sudo /usr/local/mysql/support-files/mysql.server stop

sudo mysqld_safe --skip-grant-tables

mysql -u root

UPDATE mysql.user SET Password=PASSWORD('password') WHERE User='root';

FLUSH PRIVILEGES;

q

sudo /usr/local/mysql/support-files/mysql.server start

sudo su

sudo /usr/local/mysql/support-files/mysql.server stop

mysql -u root

UPDATE mysql.user SET authentication_string=PASSWORD('new_password') WHERE User='root';

FLUSH PRIVILEGES;