Question

cot(-x)=-cotx identity

Answer 1

Its not necessarily an identity cot(x) falls under the definition of an odd function which is defined as any function such that

\[f(-x) = -f(x) \]

So, it follows that cot(-x)=-cot(x).

I hope this helps :)

Answer 2

what do you mean it follows?

Answer 3

Since, cot(-x)=-cot(x) it means it falls under the definition of an odd function.