а) 2²/₃ • x²y⁸ • (-1 ¹/₂ • xy³)⁴ = 8/3 * x²y⁸ * (-3/2 * xy³)^4 = 8/3 * x²y⁸ * 81/16 * x⁴y¹² = (8/3 * 81/16) * (x² * x⁴) * (y⁸ * y¹²) = 27/2 * x⁶ * y²⁰ = 13.5x⁶y²⁰
б) xⁿ⁻² • x³⁻ⁿ • x = xⁿ⁻²⁺³⁻ⁿ⁺¹ = x²
Ответ: а) 13.5x⁶y²⁰; б) x²