\(\dfrac{42}{46}+\dfrac{250}{186}+\dfrac{-2121}{2323}+\dfrac{-125125}{143143}\)

\(=\dfrac{21}{23}+\dfrac{125}{143}+\left(\dfrac{-21}{23}\right)+\left(\dfrac{-125}{143}\right)\)

\(=\dfrac{21}{23}+\dfrac{125}{143}-\dfrac{21}{23}-\dfrac{125}{143}\)

\(=0\)

\(\dfrac{42}{46}+\dfrac{250}{186}+\dfrac{-2121}{2323}+\dfrac{-125125}{143143}\)

\(=\dfrac{21}{23}+\dfrac{125}{93}+\dfrac{-21}{23}+\dfrac{-125}{143}\)

\(=125\left(\dfrac{1}{93}-\dfrac{1}{143}\right)\)

\(=\dfrac{6250}{13299}\)

\(\frac{42}{46}+\frac{250}{186}+\left(\frac{-2121}{2323}\right)+\left(\frac{-125125}{143143}\right)\)

\(=\frac{21}{23}+\frac{125}{93}+\left(\frac{-21}{23}\right)+\left(\frac{-125}{143}\right)\)

Đến chỗ này bạn xem lại đề nhé 

THANKS BẠN

`Answer:`

\(\frac{4}{20}+\frac{16}{42}+\frac{6}{15}-\left(-\frac{3}{21}\right)+\left(-\frac{10}{21}\right)+\frac{3}{20}\)

\(=\left(\frac{4}{20}+\frac{3}{20}+\frac{6}{15}\right)+\left(\frac{8}{21}+\frac{3}{21}-\frac{10}{21}\right)\)

\(=\frac{3}{4}+\frac{1}{21}\)

\(=\frac{67}{84}\)

\(\frac{42}{46}+\frac{250}{186}+\left(-\frac{2121}{2323}\right)+\left(-\frac{125125}{143143}\right)\)

\(=\frac{21}{23}+\frac{125}{93}+\left(-\frac{21}{23}\right)+\left(-\frac{125}{43}\right)\)

\(=\left(\frac{21}{23}+-\frac{21}{23}\right)+\left(\frac{125}{93}+-\frac{125}{43}\right)\)

\(=\frac{6250}{13299}\)

A.\(\dfrac{4}{20}\)+\(\dfrac{16}{42}\)+\(\dfrac{6}{15}\)+\(\dfrac{-3}{5}\)+\(\dfrac{2}{21}\)+\(\dfrac{-10}{21}\)+\(\dfrac{3}{20}\)

=\(\dfrac{1}{5}\)+\(\dfrac{8}{21}\)+\(\dfrac{6}{15}\)+\(\dfrac{-3}{5}\)+\(\dfrac{2}{21}\)+\(\dfrac{-10}{21}\)+\(\dfrac{3}{20}\)

=\((\dfrac{1}{5}\)+\(\dfrac{6}{15}\)+\(\dfrac{-3}{5}\)\()\)+\((\dfrac{8}{21}\)+\(\dfrac{2}{21}\)+\(\dfrac{-10}{21}\)\()\)+\(\dfrac{3}{20}\)

=\((\)\(\dfrac{1}{5}\)+\(\dfrac{2}{5}\)+\(\dfrac{-3}{5}\)\()\)+ 0 +\(\dfrac{3}{20}\)

= 0 + 0 +\(\dfrac{3}{20}\)

=\(\dfrac{3}{20}\)

B.\(\dfrac{42}{46}\)+\(\dfrac{250}{286}\)+\(\dfrac{-2121}{2323}\)+\(\dfrac{-125125}{143143}\)

=\(\dfrac{21}{23}\)+\(\dfrac{125}{143}\)+\(\dfrac{-21}{23}\)+\(\dfrac{-125}{134}\)

=\((\dfrac{21}{23}+\dfrac{-21}{23})+(\dfrac{125}{143}+\dfrac{-125}{134})\)

= 0 + 0

= 0

Chúc bạn Tran Mai học tốt nha

giúp nhanh với 

\(\frac{42}{46}+\frac{250}{186}+\frac{-2121}{2323}+\frac{-125125}{143143}\Leftrightarrow\frac{21}{23}+\frac{125}{93}+\frac{-21}{23}+\frac{-125}{143}\)

\(\Rightarrow\left(\frac{21}{23}+\frac{-21}{23}\right)+\left(\frac{125}{93}+\frac{-125}{143}\right)=\frac{17000}{3999}\)

\(\frac{4}{46}+\frac{250}{186}+\frac{-2121}{2323}+\frac{-125125}{143143}=\frac{2}{23}+\frac{125}{93}-\frac{21}{23}-\frac{125}{143}\)

\(=-0,36\)

Nhơ nha bạn.Tích mình mình tích lại

a, 4/20+16/42+6/15+-3/5+2/2+-10/21=1/5+8/21+2/5+-3/5+2/2+-16/21=(1/5+2/5+-3/5)+(8/21=-16/21)+1=-2/21+1=-19/21                       b,42/46+250/186+-2121/2323+-125125/143143                                                                                                                                =21/23+125/93+-21/23+-125/143                                                                                                                                                   =(21/23+-21/23)+(-125/143+125/93)                                                                                                                                              =6250/13299                                                             

Đề sai rồi bạn đề đúng đây :

\(\frac{42}{46}+\frac{250}{286}+\left(-\frac{2121}{2323}\right)+\left(-\frac{125125}{143143}\right)\)

\(=\frac{21}{23}+\frac{125}{143}+\left(-\frac{21}{23}\right)+\left(-\frac{125}{143}\right)\)

\(=\frac{21}{23}+\frac{125}{143}-\frac{21}{23}-\frac{125}{143}\)

\(=0\)

giờ mình biết lí do tại sao mình khồn làm được rồi

a, \(\frac{4}{20}+\frac{16}{42}+\frac{6}{15}+\frac{-3}{5}+\frac{-10}{21}+\frac{3}{20}\)

\(=\left(\frac{4}{20}+\frac{-3}{5}+\frac{6}{15}+\frac{3}{20}\right)\)\(+\left(\frac{16}{42}+\frac{2}{21}+\frac{-10}{21}\right)\)

\(=\left(\frac{4}{20}+\frac{-12}{20}+\frac{8}{20}+\frac{3}{20}\right)\)\(+\left(\frac{8}{21}+\frac{2}{21}+\frac{-10}{21}\right)\)

\(=\frac{3}{20}\)

b,\(\frac{42}{46}+\frac{250}{186}+\frac{-2121}{2323}+\frac{-125125}{143143}\)

\(=\frac{21}{23}+\frac{125}{93}+\frac{-21}{23}+\frac{-125}{143}\)

\(=\left(\frac{21}{23}+\frac{-21}{23}\right)+\left(\frac{125}{93}+\frac{-125}{143}\right)\)

\(=\frac{6250}{13299}\)