Σ(i³) = (Σi)² on Nostr: I'm feeling a little embarrassed for not getting what appears to be pretty basic ...

I'm feeling a little embarrassed for not getting what appears to be pretty basic geometry here: the absolute value distributes over the inner product, no? 
|<v,w>| = |v|•|w|, right? For v,w unit vectors that would always be =1 in any dimension, no? How does that mesh with the original \(n\) up there?

It feels like there's one small thing that'll make me slap my forehead once I get it ...