a.
81^7:3^5^2
(3⁴)^7:3^25
3^28:3^25
3³=27
b.
4^12:2^22-8^9:2^26
(2²)^12:2^22-(2³)^9:2^26
2^24:2^22-2^27:2^26
2²-2¹
4-2=2
c.
(25^2•5^4)³:5^22-25^2^2
[(5²)²•5⁴)]³:5^22-[(5²)²]
(5⁴•5⁴)³:5^22-(5⁴)²
(5^8)³:5^22-5^8
5²⁴:5²²-5^8
5²-5^8
25-5^8
Sper ca te-am ajutat!
