How is the square of LG2 equal to LG2 derived LG & # 178; 2 = (LG2) & # 178;, why and how?

How is the square of LG2 equal to LG2 derived LG & # 178; 2 = (LG2) & # 178;, why and how?

It's a rule, not a guide
LG & # 178; 2 means (LG2) & # 178; only because the former is simple