1. help with inverse tangent

Which value of a will make this true?

-2w = -arctan( w / a) ?

2. Re: help with inverse tangent

Originally Posted by hashshashin715
Which value of a will make this true?

-2w = -arctan( w / a) ?
where did this equation come from?

3. Re: help with inverse tangent

\begin{align*}-2w &=-\tan^{-1}{\left( w \over a \right)} \\2w &=\tan^{-1}{\left( w \over a \right)}\\ \tan(2w) &= \frac{w}{a} \\ a &=w \cdot \cot(2w) \end{align*}

The equation is true for $a=w\cdot \cot{(2w)}$.