\(A=\dfrac{3}{5\cdot8}+\dfrac{3}{8\cdot11}+\dfrac{3}{11\cdot14}+...+\dfrac{3}{100\cdot103}\)
\(=\dfrac{1}{5}-\dfrac{1}{8}+\dfrac{1}{8}-\dfrac{1}{11}+...+\dfrac{1}{100}-\dfrac{1}{103}\)
\(=\dfrac{98}{515}\)
Tìm x biết :
\(\dfrac{X}{2x5}+\dfrac{X}{5x8}+\dfrac{X}{8x11}+\dfrac{X}{11x14}+...+\dfrac{X}{32x35}=\dfrac{33}{70}\)
A=\(\dfrac{3}{5x8}\)+\(\dfrac{3}{8x11}\)+....+\(\dfrac{3}{2009x2012}\)
a=3/5x8+3/8x11+3/11x14+3/14x17...+3/98x101
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
1/5x8+1/8x11+1/11x14+...+1/mx(m+3)=101/1540
Tính B = \(\frac{3}{2x5}+\frac{3}{5x8}+\frac{3}{8x11}+\frac{3}{11x14}\)
Tìm a:
A= \(\dfrac{1}{1x4}\)+\(\dfrac{1}{1x7}\)+\(\dfrac{1}{7x10}\)+.....+\(\dfrac{1}{100x103}\)
