Question 1111026
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We are given {{{alpha}}} = {{{(3pi)/7}}},

angle {{{theta}}} is such that  {{{pi/2}}} < {{{theta}}} < {{{2pi}}}  and  {{{cos(alpha)}}} = {{{cos(theta)}}}.


Then  {{{theta}}} = {{{2pi - (3pi)/7}}} = {{{(14pi)/7 - (3pi)/7)}}} = {{{(11pi)/7}}}.


<U>Answer</U>.  {{{theta}}} = {{{(11pi)/7}}}.
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