1/50x51+1/51x52+...+1/99x100=1/50-1/51+1/51 - 1/52+.....+1/99 - 1/100
=1/50-1/100
= 2/100-1/100
=1/100
Nha bạn
1/50x51+1/51x52+...+1/99x100=1/50-1/51+1/51 - 1/52+.....+1/99 - 1/100
=1/50-1/100
= 2/100-1/100
=1/100
Nha bạn
Tính 1/50x51+1/51/52+........+1/98x99+1/99x100
Tính nhanh B =(1/2x3 + 1/3x4 + 1/4x5 +1/5x6 +1/6x7+1/7x8 + 1/8x9 + .... + 1/50x51) + ( 5/6 + 19/ 20 + 41/42 + 71/72 + .... + 2549/2550 )
Tính : 1/4x5 + 1/5x6 + ................. + 1/98x99 + 1/99x100
Tính A= 1/1x2+1/2x3+1/3x4+........+1/98x99+1/99x100
Tính nhanh:
1/1x2 + 1/2x3 + 1/3x4 +................+ 1/99x100.
Tính tổng
1/2x3+1/3x4+1/4x5+.....+1/99x100
Tính nhanh:
M = 1/1x2 + 1/2x3 + 1/3x4 +..............+1/99x100 =
tính tổng
A=1/1x2+1/2x3+.....+1/99x100
cần gấp nha,thanks
tính nhanh
\(\frac{1}{1x2}+\frac{1}{2x3}+\frac{1}{3x4}+\frac{1}{4x5}+....+\frac{1}{99x100}\)