Question

$\tan 25° = p \Rightarrow \: \frac{tan\, 245° + \tan\, 335° }{\tan\, 205° - \tan\, 115°} = $

• A. $\frac{p^2 -1}{p^2 +1}$
• B. $\frac{p^2 + 1 }{p^2 - 1}$
• C. $\frac{1 - p^2 }{1 + p^2 }$
• D. $\frac{ 1 + p^2 }{1 - p^2 }$

Answer 1

Answer: (C)

$\tan (245°) = \tan (270° - 25°)$
$\tan (335°) = \tan (360° -25°) $
$\tan (205°) = \tan (180° + 25°) $
$\tan (115°) = \tan (90° + 25°)$