[(3 la puterea a 7-a ×3 la puterea a 8-a - 1) : ( 27 la puterea a 5-a - 1)] la puterea a 4-a =?

Răspuns :

(3^7 • 3^8 - 1) : [(3^3)^5 - 1]^4 =
(3^15 - 1) : (3^15 - 1)^4 =
(3^15 - 1)^(-3) sau 1/(3^15 - 1)^3