Đại số lớp 6
Các câu hỏi tương tự
S=1+1/2^2+1/3^2+...+1/100^2
CMR S<2
Câu 2: CMR S<1/4 với S=1/4^2+1/6^2+...+1/(2n)^2
cmr : -1/2 + 1/3 + -1/4 + ..... + 1/199 + -1/200 = 1/101 + 1/102 + .... + 199 + 1/200
CMR
1/26 + 1/27 + 1/28+....+ 1/50 = 1 - 1/2 + 1/3 - 1/4 + ... +1/49 - 1/50
CMR : A = 1/2^3 + 1/3^3 + .................... + 1/n^3 <1/4
CMR: 100- \(\left(1+\dfrac{1}{2}+\dfrac{1}{3}+...+\dfrac{1}{100}\right)=\dfrac{1}{2}+\dfrac{2}{3}+\dfrac{3}{4}+...+\dfrac{99}{100}\)
CMR 100-(1+\(\dfrac{1}{2}+\dfrac{1}{3}+...+\dfrac{1}{100}\))= (\(\dfrac{1}{2}+\dfrac{2}{3}+\dfrac{3}{4}+...+\dfrac{99}{100}\))
B = \(\dfrac{1}{2^2}+\dfrac{1}{3^2}+\dfrac{1}{4^2}+...+\dfrac{1}{100^2}\)
CMR : B <1
Cho A=\(\frac{1}{2}-\frac{1}{3}+\frac{1}{4}-\frac{1}{5}+...+\frac{1}{98}-\frac{1}{99}\)
CMR:0,2<A<0,4
Cmr:
C=1/42 + 1/62 + 1/82 +....+ 1/(2n)2 < 1/4
D= 2!/3! + 2!/4! + 2!/5! +......+ 2!/n! < 1