Roots

Use the \sqrt{} command to produce square roots:

$\sqrt{\frac{a}{b}}$

produces

$\sqrt{\frac{a}{b}}$

If you need an nth root, use \sqrt[n]{} instead.

$\sqrt[10]{\frac{a}{b}}$

produces

$\sqrt[10]{\frac{a}{b}}$

Practice: Construct a document containing the quadratic formula and also a cube root.