Question #c7bbb

1 Answer
May 3, 2017

#x=0, x=(2pi)/3, x=pi, x=(4pi)/3#

Explanation:

#2sin2x+2sinx=0#

Use the double angle identity to simplify #color(blue)(sin(2x))#

#2(color(blue)(2sinxcosx))+2sinx=0#

#4sinxcosx+2sinx=0#

Factor:
#(2sinx)(2cosx+1)=0#

Use zero product rule to determine values:
#2sinx=0#
#sinx=0#

#x=0 , x=pi #

#2cosx+1=0#
#2cosx=-1#
#cosx=(-1)/2#

#x=(2pi)/3 , x=(4pi)/3#