Precalculus Examples

$\cos (\arccos (\frac{2}{3}))$

Step 1

The functions cosine and arccosine are inverses.

$\frac{2}{3}$

Step 2

The result can be shown in multiple forms.

Exact Form:

$\frac{2}{3}$

Decimal Form:

$0.\overline{6}$

$[\begin{array}{c} x^{2} & \frac{1}{2} \\ \sqrt{π} & \int x d x \end{array}]$