Question 680889
I'm using x instead of theta


cos(x)*sin(x) = 2/3


(1/2)*sin(2x) = 2/3


sin(2x) = 2*2/3


sin(2x) = 4/3


2x = arcsin(4/3)


Since the domain of the arcsine function is -1 <= x <= 1 and since 4/3 is greater than 1, this means that there are no solutions.