Odpowiedź:
[tex]\frac{\frac{2}{3} +\frac{1}{5} }{\frac{2}{5}-\frac{1}{2} } +(3\frac{2}{17} -4\frac{6}{13} )*(0,75-\frac{3}{4} )=\frac{\frac{10}{15}+\frac{3}{15} }{\frac{4}{10}-\frac{5}{10} } +(3\frac{2}{17} -4\frac{6}{13} )*(0,75-0,75)=\frac{\frac{13}{15} }{-\frac{1}{10} } +(3\frac{2}{17} -4\frac{6}{13}) *0=\frac{13}{15} *(-10)=-\frac{26}{3} =-8\frac{2}{3}[/tex]
b)[tex]\frac{2}{3} -[0,8*\frac{3}{(-2)^2} -\frac{(-2)^2}{5} ]:(-1\frac{1}{2} )=\frac{2}{3} -(\frac{8}{10} *\frac{3}{4} -\frac{4}{5} ):(-\frac{3}{2} )=\frac{2}{3} -(\frac{6}{10} -\frac{8}{10})*(-\frac{2}{3})=\frac{2}{3} -(-\frac{2}{10})*(-\frac{2}{3} )=\frac{2}{3}- \frac{4}{30} =\frac{20}{30} -\frac{4}{30} =\frac{16}{30} =\frac{8}{15}[/tex]
c)[tex](\frac{1}{3} -\frac{1}{2} ):(\frac{5}{3} -\frac{5}{4} )-(0,25-\frac{3}{8} :0,625)=(\frac{2}{6} -\frac{3}{6} ):(\frac{20}{12} -\frac{15}{12} )-(\frac{1}{4} -\frac{3}{8} :\frac{5}{8})=(-\frac{1}{6} ):\frac{5}{12} )-(\frac{1}{4} -\frac{3}{8} *\frac{8}{5} )=-\frac{1}{6} *\frac{12}{5} -(\frac{1}{4}-\frac{3}{5}) =-\frac{2}{5}-(\frac{5}{20} -\frac{12}{20})=-\frac{8}{20} +\frac{7}{20} =-\frac{1}{20}[/tex]
d)[tex]((-\frac{1}{2} )^2-(-\frac{1}{2} )^3):((-\frac{2}{3})^2-(-\frac{1}{3})^2)=(\frac{1}{4} +\frac{1}{8} ):(\frac{4}{9} -\frac{1}{9} )=(\frac{2}{8} +\frac{1}{8}):\frac{3}{9} =\frac{3}{8}*3=\frac{9}{8} =1\frac{1}{8}[/tex]
Szczegółowe wyjaśnienie:
w tych zadaniach ważne jest sprowadzenie ułamków do wspólnego mianownika,oraz dzielenie ułamków.Jak dzielimy ułamki tp mnożymy przez odwrotność
