Question

Which of the following has the same value as cos 2pi/3

Answer 1

First, let's calculate the value of cos 2pi/3:

`\cos(2\pi)/(3)=-0.5`

Now, let's calculate the value of each option:

`\begin{gathered} \cos(\pi)/(6)=0.866\\ \\ \\ \\ \cos(4\pi)/(3)=-0.5\\ \\ \\ \\ \sin(5\pi)/(3)=-0.866\\ \\ \\ \\ \sin(7\pi)/(6)=-0.5\\ \\ \\ \\ \cos(11\pi)/(6)=0.866 \end{gathered}`

Therefore the correct options are B and D.