## Rødder

#### Regler

 $\sqrt {a \cdot b}$ = $\sqrt {a}\cdot \sqrt{b}$ $\sqrt {3 \cdot 6}$ = $\sqrt {3}\cdot \sqrt{6}$ $\sqrt \frac{a}{b}$ = $\frac {\sqrt{a}}{\sqrt{b}}$ $\sqrt \frac{9}{3}$ = $\frac {\sqrt{9}}{\sqrt{3}}$ $^n\sqrt {a \cdot b}$ = $^n\sqrt {a}\cdot ^n\sqrt{b}$ $^2\sqrt {4 \cdot 16}$ = $^2\sqrt {4}\cdot ^2\sqrt{16}$ $^n\sqrt \frac{a}{b}$ = $\frac {^n\sqrt{a}}{^n\sqrt{b}}$ $^3\sqrt \frac{81}{3}$ = $\frac {^3\sqrt{81}}{^3\sqrt{3}}$

#### Øvelser:

$\sqrt {25 \cdot 36}$

$\sqrt {4 \cdot 9\cdot 81}$

$^3\sqrt {125 \cdot 9\cdot 27}$

$^4\sqrt {16 \cdot 9\cdot 625}$

$\sqrt \frac{1}{16}$

$\sqrt \frac{81}{121}$

$^3\sqrt \frac{1}{27}$

$^3\sqrt \frac{8}{1000}$

$^3\sqrt \frac{125}{216}$