59. Tính:
a) \(\frac{1}{8}-\frac{1}{2}\) ; b) \(\frac{-11}{12}-(-1)\) ; c) \(\frac{3}{5}-\frac{5}{6}\) ;
d) \(\frac{-1}{16}-\frac{1}{15}\) e) \(\frac{11}{36}-\frac{-7}{24}\) ; g) \(\frac{-5}{9}-\frac{-5}{12}\) .
Hướng dẫn giải.
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a) \(\frac{1}{8}-\frac{1}{2}=\frac{1}{8}+\left (-\frac{1}{2} \right )=\frac{1}{8}+\frac{-4}{8}=\frac{-3}{8}\).
b) \(\frac{-11}{12}-(-1)=\frac{-11}{12}-\left (-\frac{12}{12} \right )=\frac{-11}{12}+\frac{12}{12}=\frac{1}{12}.\)
c) \(\frac{3}{5}-\frac{5}{6}=\frac{3}{5}+\left (-\frac{5}{6} \right )=\frac{18-25}{30}=\frac{-7}{30}.\)
ĐS. d) \(\frac{-31}{240}\) ; e) \(\frac{43}{72}\) ; g) \(\frac{-5}{36}\) ;