2sinxcosx=sin2x
sin(x) = sin(2x)
sin(x) = 2sin(x)cos(x)
0 = 2sin(x)cos(x) - sin(x)
2sin(x)cos(x) - sin(x) = 0
sin(x)(2cos(x) - 1) = 0
sin(x) = 0 or 2cos(x) - 1 = 0
sin(x) = 0 or 2cos(x) = 1
sin(x) = 0 or cos(x) = 1/2
x = arcsin(0) or x = arccos(1/2)
x = pin or x = pi/3 + 2pin or x = -pi/3 + 2pin
