Find a cofunction with the same value as the given expression.
-$\tan \frac { \pi } { 17 }$
A) $\cot \frac { 15 \pi } { 34 }$
B) $\tan \frac { 15 \pi } { 34 }$
C) $\cot \frac { \pi } { 17 }$
D) $\csc \frac { \pi } { 17 }$

Question

Quizplus · Accepted Answer

The cofunction identity for tangent and cotangent is $\tan(\theta) = \cot(\frac{\pi}{2} - \theta)$. Given $\tan(\frac{\pi}{17})$, its cofunction is $\cot(\frac{\pi}{2} - \frac{\pi}{17}) = \cot(\frac{16\pi}{34} - \frac{2\pi}{34}) = \cot(\frac{14\pi}{34}) = \cot(\frac{15\pi}{34})$, which matches choice A.

Find a Cofunction with the Same Value as the Given tan⁡π17\tan \frac { \pi } { 17 }tan17π​

Find a Cofunction with the Same Value as the Given $\tan \frac { \pi } { 17 }$