How to install PAE on ubuntu mate

Hello,

I am using rapberry pi2 for my project which has 32 bit quad core ARM processor. I am using ubuntu mate OS for this. Could anyone suggest me on how to install PAE .? I have gone through this https://help.ubuntu.com/community/PAE/PentiumM link but when i use “apt-get install linux-image-generic-pae” i am getting error
E: could not open lock file /var/lib/dpkg/lock - open
E: Unable tp lock the administration directory (/var/lib/dpkg/), are you root?

Please advice

[quote=“143ubuntu, post:1, topic:2942”]
apt-get install linux-image-generic-pae
[/quote]

It should have “sudo” in front of it!:

sudo apt-get install linux-image-generic-pae

Also make sure that no other package managers like “updater” or “Synaptic” are running at the same time!.