Question

Find the two values for x(in radians between 0 & 2pii),that satisfy the equation cos x=-1/2

Answer 1

Given data:

The given expression is cosx=-1/2.

The solution of the given expression is,

`\begin{gathered} \cos x=-\cos (\pi)/(3) \\ \cos x=\cos ((2\pi)/(3)) \\ x=(2\pi)/(3)or120^(\circ) \end{gathered}`

Thus, the value of x is 2π/3 or 120 degrees.