Ответы и объяснения

2013-04-29T03:10:19+04:00

28^2n-1/2^4n-2*7^2n-2 = (4*7)^2n-1/2^4n-2*7^2n-2 = 4^2n-1*7^2n-1/4^2n-1*7^2n-2 = 7^2n-1/7^2n-2 =7^2n-1(2n-2)=7^2n-1-2n+2=7