Filling Question

\tan \dfrac{\pi}{5}+ \tan \dfrac{2\pi}{5}+\tan \dfrac{3\pi}{5}+\tan \dfrac{4\pi}{5}=

Collected in the board: Trigonometry

Steven Zheng Steven Zheng posted 1 year ago

Answer

  1. \tan \dfrac{\pi}{5}+ \tan \dfrac{2\pi}{5}+\tan \dfrac{3\pi}{5}+\tan \dfrac{4\pi}{5}=

    =\tan \dfrac{\pi}{5}+\tan \dfrac{2\pi}{5}+\tan (\pi- \dfrac{2\pi}{5}) +\tan (\pi-\dfrac{\pi}{5})

    =\tan \dfrac{\pi}{5}+\tan \dfrac{2\pi}{5}-\tan \dfrac{2\pi}{5}-\tan \dfrac{\pi}{5}

    =0

Steven Zheng Steven Zheng posted 1 year ago

Scroll to Top