[tex][( \frac{2}{3})^2 + \frac{2}{3^2} - (1\frac{1}{3} )^2] : [2 \frac{1}{7}: 1\frac{1}{2}]=[ \frac{4}{9} + \frac{2}{9} - ( \frac{4}{3} )^2] : [ \frac{15}{7}: \frac{3}{2}]=\\\\= [ \frac{4}{9} + \frac{2}{9} - \frac{16}{9} ] : [ \frac{\not{15}^5}{7}* \frac{2}{\not{3}^1} ]= (-\frac{10}{9}) : \frac{10}{7} =(-\frac{\not{10}^1}{9} )*\frac{7}{\not{10}^1}=-\frac{7}{9}[/tex]
