bỏ ngoặc:

\(\left(-\dfrac{1}{4}+\dfrac{7}{33}-\dfrac{5}{3}\right)-\left(-\dfrac{15}{12}+\dfrac{6}{11}-\dfrac{48}{49}\right)\)

so sánh:

a)\(\dfrac{-3}{-7};\dfrac{15}{-21}\)

b)\(\dfrac{2008}{2009};\dfrac{-2009}{-2008}\)

bỏ dấu ngoặc:

a)\(\left(\dfrac{18}{25}+3\dfrac{5}{11}-\dfrac{6}{17}\right)-\left(2\dfrac{5}{11}-2\right)-\left(-\dfrac{7}{25}+\dfrac{11}{17}\right)\)

b)\(\left(5-\dfrac{9}{11}+\dfrac{4}{7}\right)-\left(2+\dfrac{2}{11}-\dfrac{3}{7}\right)\)

c)\(\left(7\dfrac{1}{2}+3\dfrac{5}{9}+\dfrac{1}{3}\right)-\left(6\dfrac{1}{2}-2\dfrac{5}{9}+\dfrac{1}{3}\right)\)

d)\(\left(\dfrac{1}{6}-\dfrac{3}{5}+\dfrac{4}{3}\right)-\left(\dfrac{1}{3}+\dfrac{2}{5}\right)+\left(3-\dfrac{1}{6}\right)\)