Question

[pham thi hoa]

bài 1

a, \(\frac{-3}{7}\)-\(\left\{\frac{2}{3}-\frac{3}{7}\right\}\) b,\(\frac{2}{15}:\left[\frac{1}{3}.\frac{4}{5}-\frac{1}{3}.\frac{6}{5}\right]\)

Answer 1

[Não Gà]

a)

\(\frac{-3}{7}-(\frac{2}{3}-\frac{3}{7})\)

=\(\frac{-3}{7}-\frac{5}{21}\)

=\(\frac{-2}{3}\)

b)

\(\frac{2}{15}:(\frac{1}{3}.\frac{4}{5}-\frac{1}{3}.\frac{6}{5})\)

=\(\frac{2}{15}:[\frac{1}{3}.(\frac{4}{5}-\frac{6}{5})]\)

=\(\frac{2}{15}:(\frac{1}{3}.\frac{-2}{5})\)

=\(\frac{2}{15}:\frac{-2}{15}\)

=-1