Ответ:

  1. \(x^2\cdot x^9=x^{2+9}=x^{11}\).
  2. \(x^{11}:x^5=x^{11-5}=x^6\).
  3. \(x^{10}:x^{10}=1\), при \(x\ne0\).
  4. \((x^8)^5=x^{8\cdot5}=x^{40}\).
  5. \((x^4)^6:x^3=x^{24-3}=x^{21}\).
  6. \(\frac{x^{13}\cdot x}{x^{10}}=x^{13+1-10}=x^4\).
  7. \(x^8\cdot(x^2)^3=x^8\cdot x^6=x^{14}\).
  8. \((2x)^6=2^6x^6=64x^6\).
  9. \((3ab^5)^4=3^4a^4b^{20}=81a^4b^{20}\).
  10. \(\left(\frac a4\right)^3=\frac{a^3}{4^3}=\frac{a^3}{64}\).
  11. \(\left(\frac{4a^3}{3b^7}\right)^3=\frac{4^3a^9}{3^3b^{21}}=\frac{64a^9}{27b^{21}}\).

Ответ: а) \(x^{11}\); б) \(x^6\); в) \(1\); г) \(x^{40}\); д) \(x^{21}\); е) \(x^4\); ж) \(x^{14}\); з) \(64x^6\); и) \(81a^4b^{20}\); к) \(\frac{a^3}{64}\); л) \(\frac{64a^9}{27b^{21}}\).