Sửa đề: \(C=\dfrac{3}{5\cdot8}+\dfrac{3}{8\cdot11}+...+\dfrac{3}{128\cdot131}\)
\(=\dfrac{1}{5}-\dfrac{1}{8}+\dfrac{1}{8}-\dfrac{1}{11}+...+\dfrac{1}{128}-\dfrac{1}{131}\)
\(=\dfrac{126}{655}\)
a=3/5x8+3/8x11+3/11x14+3/14x17...+3/98x101
A=\(\dfrac{3}{5x8}\)+\(\dfrac{3}{8x11}\)+\(\dfrac{3}{11x14}\)+....+\(\dfrac{3}{100x103}\)
A=3/5x8+3/8x11+3/11x14+...+3/2009x2012 + 3/2012x2015
B = 3/2x5 + 3/5x8 + 3/8x11 + 3/11x14
tính
A= 3/5x2 + 3/5x8 + 3/8x11 +3/ 11x14
giúp mk nha
Tính B = \(\frac{3}{2x5}+\frac{3}{5x8}+\frac{3}{8x11}+\frac{3}{11x14}\)
1/5x8+1/8x11+1/11x14+...+1/mx(m+3)=101/1540
Tìm X biết \(\frac{1}{5x8}+\frac{1}{8x11}+\frac{1}{11x14}+...+\frac{1}{Xx\left(x+3\right)}=\frac{101}{1504}\)
Tìm x biết: \(\frac{1}{5X8}+\frac{1}{8X11}+\frac{1}{11X14}+.....+\frac{1}{xX\left(x+3\right)}=\frac{101}{1540}\)
2/5x8 + 2/8x11 + 2/11x14 + ... + 2/95x98
