\(\dfrac{1-\dfrac{8}{7}+\dfrac{8}{11}+\dfrac{8}{15}}{\dfrac{8}{7}-1+\dfrac{7}{11}+\dfrac{8}{15}}=\dfrac{1291}{1516}\) (Bn tính giá trị của tử và mẫu rồi tính như phân số bình thường nhé)

Haha

a, \(\dfrac{7}{22}\) - \(\dfrac{15}{23}\) + \(\dfrac{2022}{2023}\) - \(\dfrac{8}{23}\) + \(\dfrac{15}{22}\)

= ( \(\dfrac{7}{22}\) + \(\dfrac{15}{22}\)) - ( \(\dfrac{15}{23}+\dfrac{18}{23}\)) + \(\dfrac{2022}{2023}\)

= \(\dfrac{22}{22}\) - \(\dfrac{23}{23}\) + \(\dfrac{2022}{2023}\)

= 1 - 1 + \(\dfrac{2022}{2023}\)

= \(\dfrac{2022}{2023}\) 

b, - \(\dfrac{2}{11}\) + 5\(\dfrac{5}{6}\) ( 14\(\dfrac{1}{5}\) - 11\(\dfrac{1}{5}\)): 5\(\dfrac{1}{2}\)

= - \(\dfrac{2}{11}\) + \(\dfrac{35}{6}\) ( \(\dfrac{71}{5}\) - \(\dfrac{56}{5}\)) : \(\dfrac{11}{2}\)

= - \(\dfrac{2}{11}\) + \(\dfrac{35}{6}\) . \(\dfrac{15}{5}\) : \(\dfrac{11}{2}\)

= - \(\dfrac{2}{11}\) + \(\dfrac{35}{2}\) \(\times\) \(\dfrac{2}{11}\)

= - \(\dfrac{2}{11}\) + \(\dfrac{35}{11}\)

= \(\dfrac{33}{11}\)

= 3 

c, 2000 + { 20 - [ 4.2022⁰ - (3² + 5):2] }

= 2000 + { 20 - [ 4.1 - (9+5):2]}

= 2000 + { 20 - [ 4 - 14 : 2 ]}

= 2000 + { 20 - [ 4 -7]}

= 2000 + { 20 - (-3)}

= 2000 + 23

= 2023

đây mà là toán lớp 1 à.đồ dở hơi.

ban a toán lớp mấy thì  toán vậy bạn có trả lời được ko mà còn ra vẻ hả bạn 'doraemi'

dúng rồi đó ko trả lời thì thôi 

\(\dfrac{7}{15}+\left(\dfrac{-4}{11}\right)+\dfrac{8}{15}-2,5+\dfrac{7}{15}\)

\(=\dfrac{7}{15}+\left(\dfrac{-4}{11}\right)+\dfrac{8}{15}+\left(\dfrac{-5}{2}\right)+\dfrac{7}{15}\)

\(=\left(\dfrac{7}{15}+\dfrac{8}{15}+\dfrac{7}{15}\right)+\left[\left(\dfrac{-4}{11}\right)+\left(\dfrac{-5}{2}\right)\right]\)

\(=\dfrac{22}{15}+\left(\dfrac{-63}{22}\right)\)

\(=\dfrac{-461}{330}\)

\(=\dfrac{7}{15}+\dfrac{8}{15}+\dfrac{-4}{11}-\dfrac{5}{2}+\dfrac{7}{15}=\dfrac{22}{15}-\dfrac{63}{22}=-\dfrac{461}{330}\)

=7/15+8/15+(−4)/11−5/2+7/15=(22/15−63/22)=(−461)/330

\(\dfrac{-5}{9}+\dfrac{8}{15}+\dfrac{-2}{11}+\dfrac{4}{-9}+\dfrac{7}{15}\)

=\(\left(\dfrac{-5}{9}+\dfrac{-4}{9}\right)+\left(\dfrac{8}{15}+\dfrac{7}{15}\right)-\dfrac{2}{11}\)

=\(-1+1-\dfrac{2}{11}=\dfrac{-2}{11}\)

\(=\left(\dfrac{-5}{9}+\dfrac{-4}{9}\right)+\left(\dfrac{8}{15}+\dfrac{7}{15}\right)+\dfrac{-2}{11}\\ =-1+1+\dfrac{-2}{11}\\ =0+\dfrac{-2}{11}=\dfrac{-2}{11}\)

\(\dfrac{-5}{9}+\dfrac{8}{15}+\dfrac{-2}{11}+\dfrac{4}{-9}+\dfrac{7}{15}\)

\(=\left(\dfrac{-5}{9}+\dfrac{-4}{9}\right)+\left(\dfrac{8}{15}+\dfrac{7}{15}\right)+\dfrac{-2}{11}\)

\(=\dfrac{-9}{9}+\dfrac{15}{15}+\dfrac{-2}{11}\)

\(=\left(-1\right)+1-\dfrac{-2}{11}\)

\(=0+\dfrac{-2}{11}\)

\(=\) \(\dfrac{-2}{11}\)

Hicc mình hông còn tgian mấy bạn giúp minh 2 câu thui cũng đc ạk

a)  5/9 + 4/9 . 3/7 + 4/9 . 4/7

  = 5/9 + 4/9 . (3/7 + 4/7)

  = 5/9 + 4/9 . 1

  = 5/9 + 4/9

  = 1 

mình lười nghĩ lắm sorry

a)C1:=2/7:2/5

=5/7

C2:=6/7:2/5-4/7:2/5

=15/7-10/7

=5/7

b)C1:=88/30+77/30

=11/2

C2:=(8/15+7/15):2/11

=1:2/11

=11/2