Cotangent Function is Odd/Examples/2 x

Examples of Cotangent Function is Odd

$\map \cot {-2 x} = -\cot 2 x$

Proof

From Cotangent Function is Odd:

$\map \cot {-\theta} = -\cot \theta$

The result follows by setting $\theta = 2 x$.

$\blacksquare$

Sources

• 1953: L. Harwood Clarke: A Note Book in Pure Mathematics ... (previous) ... (next): $\text V$. Trigonometry: Angles larger than $90 \degrees$: Examples