Ответ:

1. a^1/3 ; 2. m-n/mn ; 3. (a^1/2 + b) / a^1/2 ; 4. a^1/3 - b^1/3

Объяснение:

1. (a^1/3 × (a^2/3 + 2)) /(a^2/3 + 2) = a^1/3

2. (m^1/4 × n^1/4 ×(m-n))/(m^5/4 × n^5/4) = m-n/mn

3. ((a^1/2 - b) × (a^1/2 + b)) / a - a^1/2 × b = ((a^1/2 - b) × (a^1/2 + b)) / a^1/2 × (a^1/2 - b) = (a^1/2 + b) / a^1/2

4. (a-b) / (a^2/3 +(ab)^1/3 + b^2/3) = ((a-b) / (a^2/3 +(ab)^1/3 + b^2/3)) × ((a^1/3 - b^1/3)/(a^1/3 - b^1/3)) = (a-b) × ((a^1/3 - b^1/3)) /a-b = a^1/3 - b^1/3