Ответ:

(5^16)•(5^7)•108^0/5^20=5^(16+7)•1/5^20=5^23/5^20=5^(23-20)=5^3=125

4)a+b=1,26•10⁴+1,05•10³=12,6•10³+1,05•10³=13,65•10³=13650

a-b=1,26•10⁴-1,05•10³=12,6•10³-1,05•10³=11,55•10³=11550

Решение:

3.

(5⁸)²×5⁷×108⁰/5²⁰ = 5¹⁶×5⁷×1/5²⁰ = 5¹⁶×5⁷/5²⁰ = 5²³/5²⁰ = 5³ = 125

4.

а) 1,26×10⁴ + 1,05×10³ = (1,26×10+1,05)×10³ = (12,6+1,05)×1000 = 13,65×1000 = 13650

б) 1,26×10⁴ - 1,05×10³ = (1,26×10-1,05)×10³ = (12,6-1,05)×1000 = 11,55×1000 = 11550