Answer:
4. B. [tex]\frac{\sqrt{2} }{3} \\[/tex]
5. C. [tex]16x^{3} \sqrt[3]{x}[/tex]
Solution:
4.
[tex]\sqrt{\frac{18}{81} } =\frac{\sqrt{18}}{\sqrt{81}} \\=\frac{3\sqrt{2} }{9} \\=\frac{\sqrt{2} }{3} \\[/tex]
5.[tex](2^{\frac{12}{5} }x^{2})^{\frac{5}{3} }[/tex]
[tex]\sqrt[3]{[(\sqrt[5]{2x^{12} } )x^{2}]^{5}} \\=\sqrt[3]{[(4\sqrt[5]{4} )x^{2}]^{5}} \\\\=\sqrt[3]{4096x^{10} }\\=16x^{3} \sqrt[3]{x}[/tex]
