You can uninstall or removes an installed libinjeqt0 package itself from Ubuntu 16.04 LTS (Xenial Xerus) through the terminal,
$ sudo apt-get remove libinjeqt0
If you would like to remove libinjeqt0 and it's dependent packages which are no longer needed from Ubuntu,
$ sudo apt-get remove --auto-remove libinjeqt0
If you use with purge options to libinjeqt0 package all the configuration and dependent packages will be removed.
$ sudo apt-get purge libinjeqt0
If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.
$ sudo apt-get purge --auto-remove libinjeqt0