How do you find the exact value of expression: #cos ((8pi)/3)#?
1 Answer
Jun 23, 2018
Explanation:
#cos((8pi)/3)#
#=cos((8pi)/3-2pi)#
#=cos((2pi)/3)=-cos(pi/3)=-1/2#
#cos((8pi)/3)#
#=cos((8pi)/3-2pi)#
#=cos((2pi)/3)=-cos(pi/3)=-1/2#