cho tong S =4/3+1/4+1/5+...+1/8+1/9
CMR1 <S<2 chu y / la phan so
Tính các tổng sau:
1, S=1-2+3_4+..+25-26
2, S=1-3+5-7+...+49-51
3, S=-1+3-5+7-...-53+55
4, S=2-4+6-8+...+22-24
5, S=-2+4-6+8-...-26+28
6, S=2-5+8-11+...-29+32
7, S=-1+5-9-13-...-41-45
8, S=1-5+9-13+...++89-93
9, S=2-4+6-8+...+202-204
10, S=1-6=11-16+21-26+...+171-176
huhu giúp mình với ạ 2h chiều nay mình phải nộp r =(((
cho s =1/22+1/3^2+1/4^2+...........+1/9^2. cmr:2/5 < s < 8/9
cho S= 1/2^2+1/3^2+1/4^2+.....+1/9^2
c/m 2/5<s<8/9
cho : S = 1/2^2 + 1/3^2 + 1/4^2 + 1/5^2 +......+ 1/9^2 chứng minh rằng 2/5 < S < 8 / 9
Cho S = 1/2^2+1/3^2+1/4^2+...+1/9^2
Tong S co la 1 so tu nhien khong?vi sao?
Cho S=1/22+1/32+1\42+....+1\92. CMR 2/5<S<8/9
S=1/2^2+1/3^2+1/4^2+1/5^2+1/6^2+...+1/9^2, chứng minh 2/5<S<8/9