giải hộ mk vs ạ x/2008-1/10-1/15+1/21....-1/120=5/8

Đáp án:

 x=2008

Giải thích các bước giải:

$\frac{x}{2008}-\frac{1}{10}-\frac{1}{15}-\frac{1}{21}-...-\frac{1}{120}=\frac{5}{8}$

$\Rightarrow \frac{x}{2008}-\frac{2}{20}-\frac{2}{30}-\frac{2}{42}-...-\frac{2}{240}=\frac{5}{8}$

$\Rightarrow \frac{x}{2008}-2(\frac{1}{20}+\frac{1}{30}+\frac{1}{42}+...+\frac{1}{240})=\frac{5}{8}$

$\Rightarrow \frac{x}{2008}-2(\frac{1}{4.5}+\frac{1}{5.6}+\frac{1}{6.7}+...+\frac{1}{15.16})=\frac{5}{8}$

$\Rightarrow \frac{x}{2008}-2(\frac{1}{4}-\frac{1}{5}+\frac{1}{5}-\frac{1}{6}+.....-\frac{1}{16})=\frac{5}{8}$

$\Rightarrow \frac{x}{2008}-2(\frac{1}{4}-\frac{1}{16})=\frac{5}{8}$

$\Rightarrow \frac{x}{2008}-\frac{3}{8}=\frac{5}{8}$

$\Rightarrow \frac{x}{2008}=1 \Rightarrow x=2008$