Các câu hỏi tương tự
Cho A=1/2*3/4*5/6*...........99/100
CMR 1/15<A<1/10
S=1/5^2 - 2/5^3 + 3/5^4 -...+99/5^100-100/5^101
CMR S<1/3^6
Tính :
A = 1 . 2 + 2 . 3 + 3 . 4 + ... + 99 . 100
B = 1 . 3 + 2 . 4 + 3 . 5 + ... + 99 . 100
C = 1 . 4 + 2 . 5 + 3 . 6 + ... + 99 . 102
D = 4 + 12 + 24 + ... + 19404 + 19800
E = 1 + 3 + 6 + 10 + ... + 4851 + 4950
\(M=\frac{1}{2}.\frac{3}{4}.\frac{5}{6}....\frac{99}{100}\). cmr 1/15 < M <1/10
D = 1/2 x 3/4 x 5/6 x 99/100 .CMR 1/15 < D < 1/10
GIúp mình với mình đang cần gấp !
Bài 1:
a) A= 1-2+3-4+5-6+...+99-100
b) B=1+2-3-4+5+6-7-8+9+10-11-12+...+97+98-99-100
CMR (1+1/3+1/5+...+1/99)-(1/2+1/4+1/6+....+ 1/100)=1/ 51+1/52+....+1/99+1/100
cmr: 3/4!+4/5!+5/6!+...+99/100! < 1/3!
cmr: 3/4!+4/5!+5/6!+...+99/100! < 1/3!