Respuesta :

olemakpadu
4pi/3 = 4*180/3 = 240

cos 240°             240° is in the third quadrant, and cos is -ve there.

cos 240 = -cos(240 - 180)
        
              = -cos60
          
              = -0.5

cos 4pi/3 = -0.5
NellySan

Answer:

-1/2

Step-by-step explanation:

The person above explained it perfectly. It's B (or -1/2) on ed2020