\(\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+\frac{1}{30}+...+\frac{1}{x\left(x+1\right) }=\frac{2015}{4034}\)
\(\frac{1}{2}-\frac{1}{x+1}=\frac{2015}{4034}\)
\(x=2016\)
\(\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+\frac{1}{30}+...+\frac{1}{x\left(x+1\right) }=\frac{2015}{4034}\)
\(\frac{1}{2}-\frac{1}{x+1}=\frac{2015}{4034}\)
\(x=2016\)
\(\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+\frac{1}{15}+...+\frac{2}{x.\left(x-1\right)}=\frac{2015}{2017}\)
Giúp mình với đáp án là 2017 hay 2018
tìm x biết :
a, \(\left[\frac{1}{2}+\frac{1}{3}+....+\frac{1}{10}\right]\cdot x=\frac{9}{1}+\frac{8}{2}+\frac{7}{3}+....+\frac{1}{9}\)
b, \(\left[\frac{1}{2}+\frac{1}{3}+....+\frac{1}{2018}\right]\cdot x=\frac{2017}{1}+\frac{2016}{2}+\frac{2015}{3}+...+\frac{1}{2017}\)
ai làm nhanh,đúng mình sẽ tích cho người đó .
Tìm x biết
\(\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+...+\frac{2}{x.\left(x+1\right)}=\frac{2015}{2017}\)
Câu 1: Tìm x biết:
a, \(\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+...+\frac{2}{x\left(x+1\right)}=\frac{2015}{2017}\)
Tìm số tự nhiên x , biết rằng :
\(\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+...+\frac{2}{x\left(x+1\right)}=\frac{2015}{2017}\)
Tìm x biết
a) \(\left(\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{2019}\right).x=\frac{2018}{1}+\frac{2017}{2}+\frac{2016}{3}+...+\frac{2}{2017}+\frac{1}{2018}\)
b) \(\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+...+\frac{2}{x\left(x+1\right)}=\frac{2017}{2019}\)
a,\(\frac{2}{3}x-\frac{3}{2}\left(x-\frac{1}{2}\right)=\frac{5}{12}\)
b,\(\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+.......+\frac{2}{x\left(x+1\right)}=\frac{2013}{2015}\)
AI GIAI DUOC MINH TICK CHO.NHO GIAI CHI TIET NHA
1. /x-5/=\(2^4\)-6
2.\(\frac{x-1}{3}+\frac{3x-5}{2}+\frac{2x}{3}+\frac{-5x+3}{9}=\frac{210}{420}\)
3.\(\left(4x-3\right)^4=\left(4^x-3\right)^2\)
4.\(\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+....+\frac{2}{x.\left(x+1\right)}=\frac{2015}{2017}\left(x\in N^{ }SAO\right)\)
\(\left(\frac{1}{2}-1\right)\left(\frac{1}{3}-1\right)\left(\frac{1}{4}-1\right)...\left(\frac{1}{1000-1}\right)\)
\(\frac{3}{2^2}.\frac{8}{3^2}.\frac{15}{4^2}...\frac{99}{10^2}\)
ai tìm đc tích này tặng ba tik