1+1+1+1+1+1.0+1 = 1.5+1.0+1 =1.5+1.0+1.1 = 1.(5+0+1) = 1.6 = 6
1+1+1+1+1+1.0+1
=1+1+1+1+1+1
=1.6
=6
chúc bạn học tốt !
T= (1-1/3).(1-1/5).(1-1/7).(1-1/9).(1-1/11).(1-1/2).(1-1/4).(1-1/6).(1-1/8).(1-1/10)
1+1+1+1+1+1+1+1+1+1+1+1+1+3+3+3+3+3+3+5+5+5+5+5+5+5+12547895+5547854-200
chứng minh rằng
1+1/3+1/5+1/7+...+1/99-(1/2+1/4+1/6+...+1/100)=1/51+1/52+...+1/100
tính
a; A = 3/4 * 8/9 * 15/16 * ..............* 9999/10000
b; B = {1 - 1/21 } * { 1 - 1/28 } * {1 - 1/36 } * .......................*{ 1 - 1326}
c; C = { 1 + 1/1*3 } * { 1 + 1 / 2*4 } * { 1 + 1/3*5} * ...........................* { 1+ 1/99*101}
CMR : 1 - 1/2 + 1/3 - 1/4 + ... + 1/1317 - 1/1318 + 1/1319 = 1/660 + 1/661 + ... + 1 / 1318 + 1319
CMR
1/26 + 1/27 + 1/28+....+ 1/50 = 1 - 1/2 + 1/3 - 1/4 + ... +1/49 - 1/50
1/5+-1/6+1/7+-1/8+1/9+1/8+-1/7+1/6+-1/5
C = (1-1/4)*(1-1/9)*(1-1/25)*......*(1-1/100)
1,Tính nhanh
a, A = 1/2 + 1/6 + 1/12 + 1/20 + 1/30 + 1/42 + 1/56 + 1/n (n+1)
2, Tính
A, 1/n - 1/n+1 , n thuộc N*
B, 1/n - 1/n+3
