-2/5 + (4/6 - 1/15) - -1/10
1/2 - (-7/3 + 2/5) + 1/8
-2/5 + (4/6 - 1/15) - -1/10
1/2 - (-7/3 + 2/5) + 1/8
\(\dfrac{-2}{5}+\left(\dfrac{4}{6}-\dfrac{1}{15}\right)-\dfrac{-1}{10}\\ =\dfrac{-2}{5}+\dfrac{3}{5}+\dfrac{1}{10}\\ =\dfrac{1}{5}+\dfrac{1}{10}\\ =\dfrac{3}{10}\\ \dfrac{1}{2}-\left(\dfrac{-7}{3}+\dfrac{2}{5}\right)+\dfrac{1}{8}\\ =\dfrac{1}{2}+\dfrac{29}{15}+\dfrac{1}{8}\\ =\dfrac{73}{30}\\ =\dfrac{73}{30}+\dfrac{1}{8}\\ =\dfrac{307}{120}\)
\(-\dfrac{2}{5}+\left(\dfrac{4}{6}-\dfrac{1}{15}\right)-\left(-\dfrac{1}{10}\right)\)
\(=-\dfrac{2}{5}+\dfrac{3}{5}+\dfrac{1}{10}\)
\(=\dfrac{1}{5}+\dfrac{1}{10}\)
\(=\dfrac{2}{10}+\dfrac{1}{10}=\dfrac{3}{10}\)
\(\dfrac{1}{2}-\left(-\dfrac{7}{3}+\dfrac{2}{5}\right)+\dfrac{1}{8}\)
\(=\dfrac{1}{2}+\dfrac{29}{15}+\dfrac{1}{8}\)
\(=\dfrac{73}{30}+\dfrac{1}{8}=\dfrac{307}{120}\)
7/11 + -9/2 - 5/-3 +1
\(\dfrac{7}{11}+\dfrac{-9}{2}-\dfrac{5}{-3}+1\\ =\dfrac{-85}{22}+\dfrac{5}{3}+1\\ =\dfrac{-145}{66}+1\\ =\dfrac{-79}{66}\)
\(\dfrac{7}{11}+-\dfrac{9}{2}-\dfrac{5}{-3}+1\)
\(=\dfrac{7}{11}-\dfrac{9}{2}+\dfrac{5}{3}+1\)
\(=\dfrac{42}{66}-\dfrac{297}{66}+\dfrac{110}{66}+\dfrac{66}{66}\)
\(=-\dfrac{79}{66}\)
\(\dfrac{7}{11}+\dfrac{-9}{2}-\dfrac{5}{-3}+1\)
\(=\dfrac{7}{11}+\dfrac{-9}{2}-\dfrac{-5}{3}+1\)
\(=\dfrac{14}{22}+\dfrac{-99}{22}-\dfrac{-5}{3}+1\)
\(=\dfrac{-85}{22}-\dfrac{-5}{3}+1\)
\(=\dfrac{-255}{66}-\dfrac{-110}{66}+1\)
\(=\dfrac{-145}{66}+1\)
\(=-\dfrac{79}{66}\)
2/1+8/11+3/11
`2/1 + 8/11 +3/11`
`= 2 + 8/11 +3/11`
`= 22/11 + 8/11 + 3/11`
`=(22+8+3)/11`
`=33/11`
`=3`
\(\dfrac{2}{1}+\dfrac{8}{11}+\dfrac{3}{11}\)
\(=2+\left(\dfrac{8}{11}+\dfrac{3}{11}\right)\)
\(=2+1=3\)
bài 7 so sánh A và B
A=2022/2023 + 2023/2024 B=2022+2023/2023+2024
13/-10 + -14/25
giải thích ra cho mik nha
\(\dfrac{13}{-10}+\dfrac{-14}{25}=\dfrac{-65}{50}+\dfrac{-28}{50}=\dfrac{-93}{50}\) (quy đồng mẫu số)
tìm x, biết:
e) \(\dfrac{2}{7-x}\)=\(\dfrac{18}{45}\) f)\(\dfrac{2x+3}{3}\)=\(\dfrac{50}{15}\) g)\(2\dfrac{x}{7}\)=\(\dfrac{75}{35}\) h)\(2\dfrac{3}{x}\)=\(\dfrac{13}{x}\)(x khác 0)
e: =>2/7-x=2/5
=>7-x=5
=>x=2
f: =>2x+3/3=10/3
=>2x+3=10
=>2x=7
=>x=7/2
g: =>(14+x)/7=15/7
=>x+14=15
=>x=1
h: =>(2x+3)/x=13/x
=>2x+3=13
=>2x=10
=>x=5
-13/7+3/5+-1/7
\(-\dfrac{13}{7}+\dfrac{3}{5}+\left(-\dfrac{1}{7}\right)\)
\(=-\dfrac{13}{7}+\left(-\dfrac{1}{7}\right)+\dfrac{3}{5}\)
\(=-\dfrac{14}{7}+\dfrac{3}{5}\)
\(=-2+\dfrac{3}{5}\)
\(=-\dfrac{10}{5}+\dfrac{3}{5}\)
\(=-\dfrac{7}{5}\)
\(\dfrac{-13}{7}+\dfrac{3}{5}+\dfrac{-1}{7}\)
\(=\left(\dfrac{-13}{7}+\dfrac{-1}{7}\right)+\dfrac{3}{5}\)
\(=\dfrac{-13+\left(-1\right)}{7}+\dfrac{3}{5}\)
\(=-2+\dfrac{3}{5}\)
\(=\dfrac{-2}{1}+\dfrac{3}{5}\)
\(=\dfrac{-10}{5}+\dfrac{3}{5}\)
\(=\dfrac{-7}{5}\)
\(\dfrac{x+2}{7}\)=\(\dfrac{-36}{28}\)
tìm x:
\(=>\left(x+2\right).28=7.\left(-36\right)\\ =>\left(x+2\right).28=-252\\ =>x+2=-252:28\\ =>x+2=-9\\ =>x=-11\)
\(\Rightarrow28.\left(x+2\right)=-36.7\)
\(\Rightarrow28x+56+252=0\)
\(\Rightarrow28x=-308\)
\(\Rightarrow x=-11\)
Tìm những từ khi soi gương là từ có nghĩa và khi không soi gương vẫn có nghĩa. VD : Tìm \(\Rightarrow\) Mít
Mn tìm 3 từ thôi cũng đc ạ