`sin (3 x + 1) = 1/2 ` `<=> [{:(3 x + 1 = ( 5pi )/6 + k 2 pi ),(3 x + 1 = ( pi )/6 + k 2 pi ):}:} (kinZZ)` `<=> [{:(3 x = ( 5pi )/6 + k 2 pi - 1),(3 x = ( pi )/6 + k 2 pi - 1):}:} (kinZZ)` `<=> [{:( x = ( 5pi )/(18) + ( k 2 pi )/3 - 1/3),( x = ( pi )/(18) + ( k 2 pi )/3 - 1/3):}:} (kinZZ)`
