Question 1036596
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{{{2*sin(3theta) + 1}}} = {{{0}}}  ---> 

{{{sin(3theta)}}}) = {{{-1/2}}}

{{{3theta}}} = {{{7pi/6 + 2k*pi}}},   k = 0. +/-1, +/-2, . . .  or/and

{{{3theta}}} = {{{11pi/6 + 2k*pi}}},  k = 0. +/-1, +/-2, . . .

=====>

{{{theta}}} = {{{7pi/18 + (2k*pi)/3}}},   k = 0. +/-1, +/-2, . . .  or/and

{{{theta}}} = {{{11pi/18 + (2k*pi)/3}}},  k = 0. +/-1, +/-2, . . .
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