Question

Find the cofunction of the expression with the same value as tan(2pi/11).

Answer 1

Answer:

The cofunction of $\tan \frac{2\pi}{11}$ is $\cot \frac{7\pi}{22}$.

Step-by-step explanation:

In trigonometry, a function is a cofunction of another if and only if $f(A) = g(B)$, where A and B are complementary angles. In this case, the complementary function of a tangent function must be a cotangent function, this is:

$\tan \frac{2\pi}{11} = \cot \left(\frac{\pi}{2} - \frac{2\pi}{11} \right)$

$\tan \frac{2\pi}{11} = \cot \frac{7\pi}{22}$

$\tan \frac{2\pi}{11} = \frac{1}{\tan \frac{7\pi}{22} }$

$0.642 = \frac{1}{1.556}$

$0.642 = 0.642$