[질문] (2^2n-1)^2이 왜 2^2n인가요

(2^2n-1)^2=2^(2n-1+2n-1)=2^4n-2이되는데,지수를2로묶으면2^2(2n-1)가되고,풀어주면(2^2)X(2^2n)X(2^-1),즉첫번째세번째것곱하면2가되므로2X2^2n,즉2^2n이됨