How do you find the exact value of $cot^-1(-sqrt3/2)$ ?

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Answer 1 · 2018-05-09T02:17:03

$arctan(-2/sqrt{3})$ is about as good as answer as any.

That one doesn't have the nice answer you might think it would.

A cotangent of $-sqrt{3}/2$ refers to a right triangle with sides $sqrt{3}$ and $2$ so hypotenuse $sqrt{7}.$

$\sqrt{3}/2$ is a common sine or cosine, but it's not a common cotangent. There's no nice form for this angle.

$arctan(-2/sqrt{3})$ is about as good as answer as any.

How do you find the exact value of cot^-1(-sqrt3/2)cot^-1(-sqrt3/2)?