MCQ
$\tan \,{20^o}\cot \,{10^o}\cot \,{50^o}$ is equal to
  • A
    $\frac{1}{{\sqrt 3 }}$
  • $\sqrt 3 $
  • C
    $\frac{{\sqrt 3 }}{4}$
  • D
    $4\sqrt 3 $

Answer

Correct option: B.
$\sqrt 3 $
b
$\tan 20 . \tan 80 . \tan 40=\tan 3(20)=\sqrt{3} \mathrm{\,\,as}$

$\tan \theta \tan (60-\theta) \tan (60+\theta)=\tan 3 \theta$

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