Answer
See the explanation
Work Step by Step
a. $9z\sqrt {8z}-3\sqrt {2z^3}$
$=18z\sqrt {2z} - 3z\sqrt {2z}$
$=(18z-3z)\sqrt {2z}$
$=15z\sqrt {2z} $
b.$(4x^{\frac{3}{5}})(x^{\frac{1}{3}})$
$=4^{\frac{3}{5} + \frac{1}{3}}$
$=4x^{\frac{14}{15}}$
c. $\sqrt[3] {\frac{16}{x^5}}=\sqrt[3] {\frac{2\times 2^3}{x^2\times x^3}}$
$=\sqrt[3] {\frac{2}{x^2}} \times \sqrt[3] {\frac{2^3}{x^3}}$
$=\sqrt[3] {\frac{2}{x^2}} \times \frac{2}{x}$
$=\frac{2}{x} \sqrt[3]{\frac{2}{x^2}}$
