Question : Problem: reset macbook root password

bought a second hand macbook and didnt know the root password. do i have to buy the os disks or can i reset it another way

Answer : Problem: reset macbook root password

then try to hold command+S when u r mac restarts it take u to single user more there u can reset u r root password using command
passwd
then enter new passwd and then chk /Users directory if u see any folder then they are existing users in you macbook u cannot login using root at GUI. so change the passwd for those username listed in /Users dir
say
passwd
and enter the new passwd.
and quit to restart your mac.
Gud luck