C=[2a^(-2/3) – 1/2 a^(3/2)]^3 Mấy chế rút gọn bt này giúp với

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1. \[\begin{array}{l}
   C = {\left( {2{a^{ – \frac{2}{3}}} – \frac{1}{2}{a^{\frac{3}{2}}}} \right)^3} = {\left( {\frac{2}{{{a^{\frac{2}{3}}}}} – \frac{1}{2}{a^{\frac{3}{2}}}} \right)^3} = {\left( {\frac{2}{{\sqrt[3]{{{a^2}}}}} – \frac{{\sqrt {{a^3}} }}{2}} \right)^3}\\
   = {\left( {\frac{2}{{\sqrt[3]{{{a^2}}}}}} \right)^3} – 3.{\left( {\frac{2}{{\sqrt[3]{{{a^2}}}}}} \right)^2}.\frac{{\sqrt {{a^3}} }}{2} + 3.\frac{2}{{\sqrt[3]{{{a^2}}}}}.{\left( {\frac{{\sqrt {{a^3}} }}{2}} \right)^2} – {\left( {\frac{{\sqrt {{a^3}} }}{2}} \right)^3}\\
   = \frac{8}{{{a^2}}} – .\frac{{12}}{{\sqrt[3]{{{a^4}}}}}.\frac{{\sqrt {{a^3}} }}{2} + \frac{6}{{\sqrt[3]{{{a^2}}}}}.\frac{{{a^3}}}{4} – \frac{{{{\left( {\sqrt {{a^3}} } \right)}^3}}}{8}\\
   = \frac{8}{{{a^2}}} – 6.{a^{\frac{3}{2} – \frac{4}{3}}} + \frac{3}{2}.{a^{\frac{3}{2} – \frac{2}{3}}} – \frac{{{a^3}}}{8}\\
   = \frac{8}{{{a^2}}} – \frac{{{a^3}}}{8} – 6{a^{\frac{1}{6}}} + \frac{3}{2}{a^{\frac{7}{3}}}.
   \end{array}\]

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