paras-d@Paras:~$ sudo dpkg --remove --purge --force-remove-reinstreq virtualbox virtualbox-qt virtualbox-5.1
dpkg: error: conflicting actions -P (--purge) and -r (--remove)

Type dpkg --help for help about installing and deinstalling packages [*];
Use 'apt' or 'aptitude' for user-friendly package management;
Type dpkg -Dhelp for a list of dpkg debug flag values;
Type dpkg --force-help for a list of forcing options;
Type dpkg-deb --help for help about manipulating *.deb files;

Options marked [*] produce a lot of output - pipe it through 'less' or 'more' !