# How do you evaluate arc cot(-2) on the Scientific Calculator?

Use $a r c \cot \left(- 2\right) = a r c \tan \left(- \frac{1}{2}\right)$
If a = cot b, tan b = 1/cot b = 1/a
Here $a r c \cot \left(- 2\right)$ is the angle whose cotangent is (-2) = angle