## Precalculus (6th Edition) Blitzer

$2$; $8$
Note that $16=2^4$. RECALL: $a^{\frac{m}{n}}=(\sqrt[n]{a})^m$. Use the rule above: $16^{\frac{3}{4}} \\=(\sqrt[4]{16})^3 \\=(\sqrt[4]{2^4})^3 \\=(2)^3 \\=8.$ Thus, the missing expressions are $2$ and $8$.