\(\left|x-\dfrac{1}{2}\right|=\dfrac{1}{5}\\ \Rightarrow\left[{}\begin{matrix}x-\dfrac{1}{2}=\dfrac{1}{5}\\x-\dfrac{1}{2}=-\dfrac{1}{5}\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=\dfrac{7}{10}\\x=\dfrac{3}{10}\end{matrix}\right.\)
5. \(3-1\dfrac{1}{2}-x+\dfrac{5}{4}=2-\left|1\dfrac{1}{8}-\dfrac{5}{12}\right|\) 6. \(3\dfrac{1}{14}-5\dfrac{1}{3}-\dfrac{4}{7}+\dfrac{11}{21}=x-\dfrac{1}{2}\) 7. \(\dfrac{11}{-40}+\dfrac{4}{5}-\left|\dfrac{3}{4}-1\dfrac{5}{12}\right|=\dfrac{3}{20}-x\)
5. \(3-1\dfrac{1}{2}-x+\dfrac{5}{4}=2-\left|1\dfrac{1}{8}-\dfrac{5}{12}\right|\) 6. \(3\dfrac{1}{14}-5\dfrac{1}{3}-\dfrac{4}{7}+\dfrac{11}{21}=-\dfrac{1}{2}\) 7. \(\dfrac{11}{-40}+\dfrac{4}{5}-\left|\dfrac{3}{4}-1\dfrac{5}{12}\right|=\dfrac{3}{20}-X\)
tìm x \(\dfrac{1-\dfrac{1}{2}+\dfrac{x}{1-\dfrac{1}{2}}}{1+\dfrac{1}{2}-\dfrac{1}{1+\dfrac{1}{2}}}=\dfrac{7}{5}\)
b) -x - 2 = \(\dfrac{5}{4}\) c) \(\dfrac{4}{3}-\left(x-\dfrac{1}{5}\right)=\left|\dfrac{-3}{10}+\dfrac{1}{2}\right|-\dfrac{1}{6}\) d) \(\dfrac{1}{3}-\left(\dfrac{2}{3}-x+\dfrac{5}{4}\right)=\dfrac{7}{12}-\left(\dfrac{5}{2}-\dfrac{13}{6}\right)\)
Tìm x bik : a. \(0,5.\left(x-\dfrac{1}{3}\right)-\dfrac{1}{2}=x+\dfrac{-4}{5}\) b. \(\dfrac{2}{3}.\left(\dfrac{1}{2}.x-\dfrac{1}{3}\right)+\dfrac{1}{2}=\dfrac{2}{3}-x\)
Tìm \(x\)
a) \(2.\left|\dfrac{1}{2}x-\dfrac{1}{3}\right|=1\dfrac{2}{5}\)
b) \(\left|\dfrac{1}{4}x-2\dfrac{1}{5}\right|=\left|0,6-\dfrac{2}{3}x\right|\)
c) \(\left|2x-\dfrac{1}{3}\right|=x+\dfrac{1}{2}\)
1) tìm x:
\(\left(\dfrac{1}{7}x-\dfrac{2}{7}\right)\left(-\dfrac{1}{5}x+\dfrac{3}{5}\right)\left(\dfrac{1}{3}x+\dfrac{4}{3}\right)=0\)
\(3\left(x-\dfrac{1}{2}\right)-5\left(2+\dfrac{3}{5}\right)=-1\dfrac{1}{5}\)
a) \((\dfrac{1}{3}-2x)^2+\dfrac{5}{4}=\dfrac{21}{16}\)
b) \(\dfrac{4-x}{3}=\dfrac{5}{2}\)
c) \(7\dfrac{1}{3}-\left|x-1\right|:2=\dfrac{5}{2}\)
\(\dfrac{x+4}{2000}+\dfrac{x+3}{2001}=\dfrac{x+2}{2002}+\dfrac{x+1}{2003}\)
1/* Chứng minh rằng:
\(\dfrac{1}{1\times2}+\dfrac{1}{3\times4}+\dfrac{1}{5\times6}+...\dfrac{1}{49\times50}=\dfrac{1}{26}+\dfrac{1}{27}+\dfrac{1}{28}+..+\dfrac{1}{50}\)
2/* Cho:
A=\(\dfrac{1}{1\times2}+\dfrac{1}{3\times4}+\dfrac{1}{5\times6}+.....+\dfrac{1}{99\times100}\). Chứng minh rằng:\(\dfrac{7}{12}< A>\dfrac{5}{6}\)
Các bn giúp mk những bài này nha!
