Explicație pas cu pas:
a)
[tex]b = - 0.(6) = - \frac{6}{9} {}^{(3} = - \frac{2}{3} [/tex]
[tex]opusul \: lui \: b \: = - ( - \frac{2}{3} ) = \huge\boxed{\frac{2}{3} }[/tex]
b)
[tex]a = \frac{2}{9} \\ inversul \: lui \: a \: = \frac{9}{2} = \boxed{ \huge{ 4.5}}[/tex]
c)
[tex]ma = \frac{a + b}{2} \\ = \frac{ \frac{2}{9} - {}^{3)} \frac{2}{3} }{2} = \\ = \frac{ \frac{2}{9} - \frac{6}{9} }{2} = \frac{ - \frac{ 4}{9} }{2} = - \frac{ 4}{18} {}^{(2} = \huge \boxed{-\frac{2}{9} }[/tex]
