1. The problem statement, all variables and given/known data "Use the binomial expansion to derive the following results for values of v << c. a) γ ~= 1 + 1/2 v2/c2 b) γ ~= 1 - 1/2 v2/c2 c) γ - 1 ~= 1 - 1/γ =1/2 v2/c2" (where ~= is approximately equal to) 2. Relevant equations As far as I can tell, just γ = (1-v2/c2)-1/2 3. The attempt at a solution Basically, I have no idea where to apply the v << c approximation, other than right after an expansion (keeping the first few terms and dropping the rest, if it were something like (c+v)n so all I have really is circular math starting with 1-v2/c2 and ending with c2-v2.. which doesn't help. for example.. γ = (1-v2/c2)-1/2 γ-2 = 1 - v2/c2 at this point I would multiply by c2 or c, and attempt to continue, but I can't figure out what to do. Just a hint on where to go would be greatly appreciated.