Can I upgrade the RAM on my 2011 MacBook Pro
Yes, the mentioned model of MacBook Pro is user upgradable.

The maximum RAM supported by the Late 2011 MacBook Pro is 16 GB. You can refer to the specifications for this model here:


Table of second generation MacBook Pro models


Look for the column corresponding to the mentioned model (Late 2011).


  Memory &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 4 GB (two 2 GB)
  
  (Two slots) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Expandable to 16 GB