Question

$\tan 25°=p\Rightarrow \frac{tan245°+\tan 335°}{\tan 205°-\tan 115°}=$

• 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)

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