A=(∛(a^4 )+∛(a^2 b^2 )+∛(b^4 ))/(∛(a^2 )+∛ab+∛(b^2 ))

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1. Giải thích các bước giải:

   \[\begin{array}{l}
   A = \frac{{\sqrt[3]{{{a^4}}} + \sqrt[3]{{{a^2}{b^2}}} + \sqrt[3]{{{b^4}}}}}{{\sqrt[3]{{{a^2}}} + \sqrt[3]{{ab}} + \sqrt[3]{{{b^2}}}}} = \frac{{\left( {\sqrt[3]{{{a^2}}} – \sqrt[3]{{{b^2}}}} \right)\left( {\sqrt[3]{{{a^4}}} + \sqrt[3]{{{a^2}{b^2}}} + \sqrt[3]{{{b^4}}}} \right)}}{{\left( {\sqrt[3]{{{a^2}}} – \sqrt[3]{{{b^2}}}} \right)\left( {\sqrt[3]{{{a^2}}} + \sqrt[3]{{ab}} + \sqrt[3]{{{b^2}}}} \right)}} = \frac{{{{\left( {\sqrt[3]{{{a^2}}}} \right)}^3} – {{\left( {\sqrt[3]{{{b^2}}}} \right)}^3}}}{{\left( {\sqrt[3]{a} + \sqrt[3]{b}} \right)\left[ {\left( {\sqrt[3]{a} – \sqrt[3]{b}} \right)\left( {\sqrt[3]{{{a^2}}} + \sqrt[3]{{ab}} + \sqrt[3]{{{b^2}}}} \right)} \right]}}\\
    = \frac{{{a^2} – {b^2}}}{{\left( {\sqrt[3]{a} + \sqrt[3]{b}} \right)\left( {a – b} \right)}} = \frac{{a + b}}{{\left( {\sqrt[3]{a} + \sqrt[3]{b}} \right)}} = \left( {\sqrt[3]{{{a^2}}} + \sqrt[3]{{ab}} + \sqrt[3]{{{b^2}}}} \right)
   \end{array}\]

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