Question

найдите значение выражения:$\frac{1-m^{2}}{3m^{2}-m}$ при m=$\frac{2}{3}$

Answer 1

$\frac{1 - {m}^{2} }{3 {m}^{2} - m} = \frac{(1 - m)( 1 + m)}{m(3m - 1)} = \frac{(1 + \frac{2}{3} )(1 - \frac{2}{3}) }{ \frac{2}{3} (3 \times \frac{2}{3} - 1)} = \frac{ \frac{5}{3} \times \frac{1}{3} }{ \frac{2}{3} \times 1 } = \frac{5}{9} \div \frac{2}{3} = \frac{5}{9} \times \frac{3}{2} = \frac{5}{6}$