ta có:\(\frac{x-1}{x+2}=\frac{x-2}{x+3}\Rightarrow\left(x-1\right)\times\left(x+3\right)=\left(x+2\right)\times\left(x-2\right)\)
\(\Rightarrow\) \(x^2-x+3x-3=x^2+2x-2x-4\)
\(\Rightarrow\) \(x^2+2x-3=x^2-4\)
\(\Rightarrow\) \(x^2-x^2+2x=3-4\)
\(\Rightarrow\) \(2x=-1\)
\(\Rightarrow x=-1:2\)
\(\Rightarrow x=\frac{-1}{2}\)
Tim x
\(\frac{x+2015}{5}+\frac{x+2016}{4}=\frac{x+2017}{3}+\frac{x+2018}{2}\)
2/ tim x
\(\frac{x+2015}{5}+\frac{x+2016}{6}=\frac{x+2017}{7} +\frac{x+2018}{8}\)
3/ tim x
\(\frac{1}{3}+\frac{1}{6}+\frac{99}{101}+\frac{1}{15}+... +\frac{1}{x\left(2x+1\right)}=\frac{1}{10}\)
Tim x,y,z biết:
\(\frac{x+z+2}{x}=\frac{x+z+3}{y}=\frac{x+z+5}{z}=\frac{2}{x+y+z}\)
Tim x biết
\(\frac{3}{x-2}\)=\(\frac{-2}{\frac{1}{8}}\)
tim x
\(\frac{2^x+2^{x+1}+2^{x+2}}{7}=\frac{3^x+3^{x+1}+3^{x+2}}{13}\)
tim x :
\(\frac{5}{2}.x-\frac{1}{3}.x+2=\frac{3}{2}\)
Tim x biết \(\left|x+\frac{1}{2}\right|+\left|x+\frac{1}{6}\right|+\left|x+\frac{1}{12}\right|+...+\left|x+\frac{1}{110}\right|=11x\)
tim x biết \(\frac{x-1}{2}=\frac{3}{4}\)
tim x biet
a.\(\frac{x+1}{10}+\frac{x+1}{11}=\frac{x+1}{12}=\frac{x+1}{13}+\frac{x+1}{14}\)
b.\(\frac{x+4}{1990}+\frac{x+3}{1991}=\frac{x+2}{1992}+\frac{x+1}{1993}\)
\(\frac{x-1}{2009}+\frac{x-2}{2008}=\frac{x-3}{2007}+\frac{x-4}{2006}\)tim x