Đáp án:
\(D = \dfrac{4}{{13}}\)
Giải thích các bước giải:
\(\begin{array}{l}
D = - \dfrac{2}{7}.6.\dfrac{5}{{13}} - \dfrac{2}{7}.\dfrac{8}{{13}} + \dfrac{8}{7}\\
= \dfrac{2}{7}.\left( { - \dfrac{{30}}{{13}} - \dfrac{8}{{13}} + 4} \right)\\
= \dfrac{2}{7}.\dfrac{{14}}{{13}} = \dfrac{4}{{13}}\\
E = \dfrac{{92}}{9} + \dfrac{{12}}{5} - \dfrac{{65}}{9}\\
= \left( {\dfrac{{92}}{9} - \dfrac{{65}}{9}} \right) + \dfrac{{12}}{5}\\
= 3 + \dfrac{{12}}{5} = \dfrac{{27}}{5}\\
F = \dfrac{{63}}{{10}} - \dfrac{{25}}{7} + \dfrac{{23}}{{10}}\\
= \left( {\dfrac{{63}}{{10}} + \dfrac{{23}}{{10}}} \right) - \dfrac{{25}}{7}\\
= \dfrac{{43}}{5} - \dfrac{{25}}{7} = \dfrac{{176}}{{35}}
\end{array}\)
