\(\dfrac{-4}{50}\text{=}\dfrac{-2}{25}\)

\(\dfrac{6}{25}\text{=}\dfrac{6}{25}\)

\(\dfrac{-27}{54}\text{=}\dfrac{-1}{2}\)

\(\dfrac{-18}{-75}\text{=}\dfrac{6}{25}\)

\(\dfrac{28}{-56}\text{=}-\dfrac{1}{2}\)

suy ra chỉ có phân số \(\dfrac{-4}{50}\) là không bằng phân số nào trong các phân số còn lại

-1/2

\(\dfrac{6}{25}\)

\(-\dfrac{4}{50}=\dfrac{-2}{25}\)

\(-\dfrac{27}{54}=-\dfrac{1}{2}\)

\(-\dfrac{18}{75}=-\dfrac{6}{25}\)

\(\dfrac{28}{-56}=-\dfrac{1}{2}\)

\(TC:\)

\(-\dfrac{27}{54}=\dfrac{28}{-56}\)

\(a.\)

\(\dfrac{17}{8}:\left(\dfrac{27}{8}+\dfrac{11}{2}\right)\)

\(=\dfrac{17}{8}:\left(\dfrac{27+44}{8}\right)=\dfrac{17}{8}:\dfrac{71}{8}=\dfrac{17}{8}\cdot\dfrac{8}{71}=\dfrac{17}{71}\)

\(b.\)

\(\dfrac{28}{15}\cdot\dfrac{1}{4^2}\cdot3+\left(\dfrac{8}{15}-\dfrac{69}{60}\cdot\dfrac{5}{23}\right):\dfrac{51}{54}\)

\(=\dfrac{28}{15}\cdot\dfrac{1}{4^2}\cdot3+\left(\dfrac{8}{15}-\dfrac{1}{4}\right):\dfrac{51}{54}\)

\(=\dfrac{28}{15}\cdot\dfrac{1}{4^2}\cdot3+\left(\dfrac{8\cdot4-15}{60}\right):\dfrac{51}{54}\)

\(=\dfrac{28}{15}\cdot\dfrac{1}{4^2}\cdot3+\dfrac{17}{60}:\dfrac{51}{54}\)

\(=\dfrac{28}{15}\cdot\dfrac{1}{16}\cdot3+\dfrac{17}{60}\cdot\dfrac{54}{51}\)

\(=\dfrac{7}{20}+\dfrac{3}{10}\)

\(=\dfrac{7+3\cdot2}{20}=\dfrac{13}{20}\)

Sai kìa phải bằng 11/20

-2/15

-4/35

-5/3

10

-8/3

-7/2

-9

-4/3

Chúc em học giỏi

\(=\dfrac{-2}{15}\\ =\dfrac{-4}{35}\\ =-1\\ =10\\ =\dfrac{-8}{3}\\ =-7\\ =-9\\ =\dfrac{-4}{3}\)

Ta có: \(\dfrac{x-1}{59}+\dfrac{x-2}{58}+\dfrac{x-3}{57}=\dfrac{x-4}{56}+\dfrac{x-5}{55}+\dfrac{x-6}{54}\)

\(\Leftrightarrow\dfrac{x-60}{59}+\dfrac{x-60}{58}+\dfrac{x-60}{57}-\dfrac{x-60}{56}-\dfrac{x-60}{55}-\dfrac{x-60}{54}=0\)

\(\Leftrightarrow x-60=0\)

hay x=60

a) \(\dfrac{x}{-7}=14249\)

⇒ \(x=\dfrac{-14249}{7}\)

\(E=\left[\dfrac{1919}{2121}-\dfrac{54}{99}+\left(\dfrac{2456}{3799}\right)^5\right].\left(\dfrac{1}{2}-\dfrac{1}{3}-\dfrac{1}{6}\right)\)

E \(=\left[\dfrac{1919}{2121}-\dfrac{54}{99}+\left(\dfrac{2456}{3799}\right)^5\right].0\)

E = 0

Vậy E = 0

=0

-11/12

-11/12