[Toán 6]Phân số.

B

biopro

Last edited by a moderator:
N

ngbinhkhiembh

Nèk, 1-1/2+1/3-.....-1/2010
=(1+1/3+....+1/2009)-(1/2+1/4+....+1/2010)
Cộng 2 vế cho vế 2 ta có:
=(1+1/3+....+1/2009+1/2+...+1/2010)-2(1/2+1/4+....+1/2010)
=(1+1/2+1/3+....+1/2009+1/2010)-(1+1/2+...+1/1005)
=1/1006+1/1007+.....+1/2010
Nhớ thanks nhá!
 
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