Question

Срочно!
17. Найдите значение выражения
А) 3-²×5-³/15-³
Б)27-²×4-¹/6-⁵
С)81²×6-⁴×21-⁴/14‐⁵
18.упростите
А)2аб-³×5а-²б
Б)3 1/3 а⁵б-¹⁶×0,6а-¹б¹⁸
С)2,4а‐⁵б²÷(0,2а-³б‐2)

Answer 1

Ответ:

17.

А) 3⁻² × 5⁻³ / 15⁻³ = (1/3²) × (1/5³) / (1/15³) = (1/9) × (1/125) / (1/3375) = 1/9 × 125/1 × 3375/1 = 125/9 × 1/3375 = 125/30375 = 1/243.

Б) 27⁻² × 4⁻¹ / 6⁻⁵ = (1/27²) × (1/4¹) / (1/6⁵) = (1/729) × 4 / (1/7776) = 4/729 × 7776/1 = 31104/729.

С) 81² × 6⁻⁴ × 21⁻⁴ / 14⁻⁵ = (81² × 6⁻⁴ × 21⁻⁴) / 14⁻⁵ = (3⁴ × 6⁻⁴ × 21⁻⁴) / 14⁻⁵ = 3⁴ × (6/21)⁴ / 14⁻⁵ = 3⁴ × (2/7)⁴ / 14⁻⁵ = 3⁴ × (16/2401) / (1/537824) = (81/2401) × 537824 = 18270048/2401.

18.

А) 2ab⁻³ × 5a⁻²b = 2 × 1/(ab³) × 5 × 1/(a²b) = 10 / (a³b⁴).

Б) 3 1/3 а⁵б⁻¹⁶ × 0,6а⁻¹б¹⁸ = (10/3) × (6/10) × (а⁵/а⁻¹) × (б⁻¹⁶/б¹⁸) = 2а⁶б⁻³⁴/3.

С) 2,4а⁻⁵б² ÷ (0,2а⁻³б⁻²) = (2.4) × (a⁻⁵/a⁻³) × (b²/b⁻²) = 9a⁻²b⁴.