6. (1+x)⁹ = C(9,0) * 1⁹ * x⁰ + C(9,1) * 1⁸ * x¹ + C(9,2) * 1⁷ * x² + C(9,3) * 1⁶ * x³ + C(9,4) * 1⁵ * x⁴ + C(9,5) * 1⁴ * x⁵ + C(9,6) * 1³ * x⁶ + C(9,7) * 1² * x⁷ + C(9,8) * 1¹ * x⁸ + C(9,9) * 1⁰ * x⁹
= 1 + 9x + 36x² + 84x³ + 126x⁴ + 126x⁵ + 84x⁶ + 36x⁷ + 9x⁸ + x⁹
Ответ: $$1 + 9x + 36x^2 + 84x^3 + 126x^4 + 126x^5 + 84x^6 + 36x^7 + 9x^8 + x^9$$