Prove ||u+v||^2 + ||u-v||^2=2||u||^2+2||v||^2
* This is the part I can't figure out*
The Attempt at a Solution
anybody got an idea where I can start? I can't seem to remember the property I can use to simplify ||u+v||^2
P.S sorry for the vague title, i really didn't know what to put in there.