Question

EXERCIȚIUL 7 VĂ ROG!

(+Corona)

Answer 1

$\displaystyle a)~\frac{5}{6} -\frac{^{2)}2}{3} =\frac{5-2\cdot 2}{6} =\frac{5-4}{6}=\frac{1}{6} \\\\ 1\frac{1}{8} =\frac{1\cdot 8+1}{8} =\frac{8+1}{8} =\frac{9}{8} \Rightarrow inversul=\frac{8}{9} \\\\ \frac{1}{6} \cdot \frac{8}{9} =\frac{8}{54 } =\frac{4}{27}$

$\displaystyle b)~\frac{^{3)}2}{5} +\frac{3}{15} =\frac{3\cdot2+3}{15}=\frac{6+3}{15} =\frac{9^{(3}}{15} =\frac{3}{5} \Rightarrow inversul=\frac{5}{3} \\\\ \frac{3}{10} \cdot \frac{5}{3} =\frac{15^{(15}}{30} =\frac{1}{2}$

$\displaystyle c)~\frac{^{4)}1}{3} +\frac{^{3)}1}{4} =\frac{4 \cdot1+3\cdot1}{12} =\frac{4+3}{12} =\frac{7}{12} \\\\ ^{6)}2-\frac{5}{6} =\frac{6\cdot2-5}{6} =\frac{12-5}{6} =\frac{7}{6} \Rightarrow inversul=\frac{6}{7} \\\\ \frac{\not7}{12} \cdot \frac{6}{\not7} =\frac{6^{(6}}{12}=\frac{1}{2}$