Bài 2:
a: \(A+\dfrac{-5}{12}+\dfrac{5}{12}+\dfrac{6}{11}+\dfrac{5}{11}+\dfrac{7}{17}=1+\dfrac{7}{17}=\dfrac{24}{17}\)
b: \(B=\dfrac{9}{16}-\dfrac{8}{27}+1+\dfrac{7}{16}-\dfrac{19}{27}=1-1+1=1\)
c: \(C=\dfrac{21}{31}-\dfrac{16}{7}+\dfrac{44}{53}+\dfrac{10}{31}+\dfrac{9}{53}\)
\(=1+1-\dfrac{16}{7}=-\dfrac{2}{7}\)
giúp mình cả bài 1 nữa đc ko ạ mình đang cần gấp lắm ạ