Precalculus Examples

$\cot (\arccos (2))$

Step 1

The equation for cosine is $\cos (A) = \frac{Adjacent}{Hypotenuse}$ . The inside trig function is $\arccos (2)$ , which means $\cos (A) = 2$ . Comparing $\cos (A) = \frac{Adjacent}{Hypotenuse}$ with $\cos (A) = 2$ , find $Adjacent = 2$ and $Hypotenuse = 1$ . Then, using the pythagorean theorem, find $Opposite = i \sqrt{3}$ .

$Adjacent = 2$

$Opposite = i \sqrt{3}$

$Hypotenuse = 1$

Step 2

Substitute in the known variables for the equation $\cot (A) = \frac{Adjacent}{Opposite}$ .

$\cot (A) = \frac{2}{i \sqrt{3}}$

Step 3

Simplify.

$- 1.15470053 i$