2) 4,8x⁸y⁷ - (12x⁶y⁶ - 6) - 2,4x⁶y⁵(2x²y² - 5y + 3) = 4,8x⁸y⁷ - 12x⁶y⁶ + 6 -
- 4,8x⁶⁺²y⁵⁺² + 12x⁶y⁵⁺¹ - 7,2x⁶y⁵ = 4,8x⁸y⁷ - 12x⁶y⁶ + 6 - 4,8x⁸y⁷ + 12x⁶y⁶ - -7,2x⁶y⁵ = 6 - 7,2x⁶y⁵
4) 9a²⁰b¹⁶ - 1,8a¹⁰b¹⁸ - 0,9a⁵b⁹(10a¹⁵b⁷ + 2a⁵b⁹) = 9a²⁰b¹⁶ - 1,8a¹⁰b¹⁸ -
- 9a⁵⁺¹⁵b⁹⁺⁷ - 1,8a⁵⁺⁵b⁹⁺⁹ = 9a²⁰b¹⁶ - 1,8a¹⁰b¹⁸ -9a²⁰b¹⁶ - 1,8a¹⁰b¹⁸ = - 3,6a¹⁰b¹⁸