Evaluate: `tan(2tan^(-1)(1/5))`

Explanation

`\tan [2 \tan ^{-1}(\frac{1}{5})]`
`\tan [\tan ^{-1}(\frac{2(\frac{1}{5})}{1-\frac{1}{25}})]] `



`\tan [\tan ^{-1}(\frac{2}{5} \times \frac{25}{24})]`




`\tan ^{-1}(\tan \theta)=\theta \forall \theta \in(-\frac{\pi}{2}, \frac{\pi}{2})]`




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