Các câu hỏi tương tự
Giúp mình với:
Cho A=1/1×2^2+1/2×3^2+1/3×4^2+...+1/99×100^2. CMR A<4/9
CMR:
a)1/10^2 +1/11^2+1/12^2+...+1/100^2 >3/4
b)1/2^2+1/3^2+1/4^2+...+1/100^2<99/100
c)1/2^2+1/3^2+1/4^2+...+1/100^2<3/4
Bài 4 :
a,Cho A= 1/2!+1/3!+.....+1/100!
CMR A<1
b, CMR :1-1/2+1/3-1/4+...+1/99-1/100=1/51+1/52+....+1/100
CMR:
a)1/2-1/4+1/8-1/16+1/32-1/64<1/3
b)1/3 - 2/3^2 + 3/3^3 - 4/3^4 +...+ 99/3^99 -100/3^100 < 3/16
cmr
a) 1/2 -1/4+1/8-1/16+1/32-1/64 <1/3
b) 1/3-2/3^2+3/3^3-4/3^4+...+99/3^99-100/3^100<3/16
CMR:(1+1/2+1/3+1/4+...+1/100)=1/2=2/3+3/4+...+99/100
Tính:
A=1*2*3+2*3*4+3*4*5+......+98*99*100
CMR:
A=1/4+1/16+1/36+1/64+1/100+1/144+1/196<1/2
Cho A=1/2^2+1/3^2+1/4^2+...+1/100^2. CMR: A<3/4
CMR: A=1/2^2+1/3^2+1/4^2+...+1/100^2<1