a) l-ai rezolvat
b) 32 × 93 - 32 × 85 =
= 32×(93-85) =
= 32 × 8 =
= 256 =
= 16^2
c) 2^83 -4^41 =
= 2^83 - (2^2)^41 =
= 2^83 - 2^82 =
= 2^82(2-1) =
= 2^82 =
= (2^41)^2
d) 11 × (5^21-5^20-5^18) =
= 11×5^18×(5^3 - 5^2- 1) =
= 11 × 5^18 × (125-25-1) =
= 11×5^18 × 99 =
= 1089 × 5^18 =
= 33^2 × (5^9)^2 =
= (33×5^9)^2
