ayuda por favor para hoy

Respuesta:
Explicación paso a paso:
17 )
[tex]\sqrt[3]{\frac{2}{5}}.\sqrt[3]{\frac{4}{25}}\\\\=\sqrt[3]{\frac{2}{5}\cdot \frac{4}{25}}\\\\=\sqrt[3]{\frac{8}{125}}\\\\=\frac{2}{5}[/tex]
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21 )
[tex]\frac{\sqrt{\frac{12}{15}}.\sqrt{\frac{12}{15}}}{\sqrt[3]{-\frac{1}{64}}}\\\\\frac{\sqrt{\frac{12}{15}}\sqrt{\frac{12}{15}}}{\sqrt[3]{-\frac{1}{64}}}\\\\=\frac{\frac{12}{15}}{-\sqrt[3]{\frac{1}{64}}}\\\\\\=-\frac{12}{15\sqrt[3]{\frac{1}{64}}}\\\\\\=-\frac{4}{5\cdot \frac{1}{4}}\\\\\\=-\frac{4}{\frac{5}{4}}\\\\=-\frac{16}{5}[/tex]
saludos!!