A) (a⁵)³÷a¹⁰·a = a¹⁵÷a¹⁰·a = a¹⁵⁻¹⁰⁺¹ = a⁶
б) xy²-13xy²+5xy² = 1xy²-13xy²+5xy² = (1-13+5)xy² = -7xy²
в) (3x³y⁴)³ 3³·(x³)³·(y⁴)³ 27x⁹y¹²
(3x³y⁴)³÷(3xy²)² = -------- = --------------- = --------- = 3x⁷y⁸
(3xy²)² 3²·x²·(y²)² 9x²y⁴
г) (z⁹)⁴ z⁹·⁴ z³⁶ z³⁶ z³⁶
------ = -------- = ------- = -------- = ----- = 1
z(z⁵)⁷ z·z⁵·⁷ z·z³⁵ z³⁵⁺¹ z³⁶