Ответ:

Используем свойства степеней: \(a^m\cdot a^n=a^{m+n}\), \(\frac{a^m}{a^n}=a^{m-n}\), \((a^m)^n=a^{mn}\).

  1. \(a^{\frac12}\cdot a^{-\frac14}=a^{\frac12-\frac14}=a^{\frac14}\).
  2. \(\frac{x^{\frac34}\cdot x^{\frac12}}{x^{\frac14}}=x^{\frac34+\frac12-\frac14}=x\).
  3. \((c^{\frac23})^3\cdot c^{-\frac32}=c^2\cdot c^{-\frac32}=c^{\frac12}\).
  4. \((81m^{-4})^{\frac34}=81^{\frac34}m^{-3}=27m^{-3}=\frac{27}{m^3}\).
  5. \(\frac{d^{5.2}\cdot d^{-4.8}}{d^{2.3}\cdot d^{-2.7}}=d^{5.2-4.8-2.3+2.7}=d^{0.8}=d^{\frac45}\).
  6. \(b^{\frac13}\cdot b^{-\frac14}=b^{\frac13-\frac14}=b^{\frac1{12}}\).
  7. \(\frac{y^{\frac23}\cdot y^{-1}}{y^{\frac13}}=y^{\frac23-1-\frac13}=y^{-\frac23}=\frac1{y^{\frac23}}\).
  8. \((a^{\frac34})^4\cdot a^{-\frac32}=a^3\cdot a^{-\frac32}=a^{\frac32}\).
  9. \((27n^{-3})^{\frac13}=27^{\frac13}n^{-1}=\frac3n\).
  10. \(\frac{a^{3.2}\cdot a^{-2.8}}{a^{-2.6}\cdot a^{-2}}=a^{3.2-2.8+2.6+2}=a^5\).

Ответ: а) \(a^{\frac14}\); б) \(x\); в) \(\sqrt c\); г) \(\frac{27}{m^3}\); д) \(d^{\frac45}\); е) \(b^{\frac1{12}}\); ж) \(\frac1{y^{\frac23}}\); з) \(a^{\frac32}\); и) \(\frac3n\); к) \(a^5\).