1/1x4+1/2x6+1/3x8+.....+1/99x200 = ?
Tính :
A = \(\frac{5}{3x8}+\frac{8}{8x16}+\frac{1}{16x3}+\frac{1}{24x7}+\frac{1}{28x8}+\frac{1}{32x5}\)
Tính nhanh:
\(\frac{1}{1x4}+\frac{1}{4x7}+\frac{1}{7x10}+...+\frac{1}{97x100}\)
\(\frac{1}{1x4}+\frac{1}{4x7}+\frac{1}{7x10}+.......+\frac{1}{77x80}\)
giúp mình nha
Ai nhanh mình sẽ tick
Cho: S=\(\frac{3}{1x4}+\frac{3}{4x7}+\frac{3}{7x10}+...+\frac{3}{100x103}\). Chứng minh S<1
1 + \(\frac{1}{2}\)+ \(\frac{1}{3}\)+ \(\frac{1}{4}\)+ ..... + \(\frac{1}{9}\)+ \(\frac{1}{10}\)
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\(\frac{1}{1x10}\)+ \(\frac{1}{2x9}\)+\(\frac{1}{3x8}\)+.....+\(\frac{1}{9x2}\)+\(\frac{1}{10x1}\)
Giải giúp mình với, mình đang cần gấp !!!
1. \(\frac{3}{1X4}+\frac{3}{4X7}+\frac{3}{7X10}+.........+\frac{3}{40X43}\)
2. \(\frac{2}{2}+\frac{2}{6}+\frac{2}{12}+........+\frac{2}{90}\)
Giúp mk nha ai lm nhanh mk tick cho
Cái dâu X là dấu nhân nha
D=\(\frac{3}{1x4}+\frac{3}{4x7}+\frac{3}{7x10}+.......+\frac{3}{97x100}\)
Bài 3 :
D = \(\frac{2}{1x4}+\frac{2}{4x7}+\frac{2}{7x10}+...+\frac{2}{97x100}\)