1+3=4
k mih nha
mih am nhieu lam
ai k mih
mih se k lai
1 + 3 = 4 bạn à. nhớ nick cho mình nhé
\(M=\frac{2^3-1}{2^3+1}.\frac{3^3-1}{3^3+1}.\frac{4^3-1}{4^3+1}....\frac{100^3-1}{100^3+1}\)
CHỨNG MINH M> 2/3
Tính tổng: \(F=\left(1+\frac{1}{\sqrt[3]{2}}\right)\left(1+\frac{1}{\sqrt[3]{2}}+\frac{1}{\sqrt[3]{3}}\right)\left(1+\frac{1}{\sqrt[3]{2}}+\frac{1}{\sqrt[3]{3}}+\frac{1}{\sqrt[3]{4}}\right)...\left(1+\frac{1}{\sqrt[3]{2}}+\frac{1}{\sqrt[3]{3}}+\frac{1}{\sqrt[3]{4}}+...+\frac{1}{\sqrt[3]{9}}\right)\)
Chứng minh rằng
\(\dfrac{1}{26.2^3-4^3-0^3}+\dfrac{1}{26.3^3-5^3-1^3}+\dfrac{1}{26.4^3-6^3-2^3}+...+\dfrac{1}{26.2020^3-2022^3-2018^3}< \dfrac{1}{96}\)
1) \(\dfrac{2}{\sqrt{5}-2}+\dfrac{-2}{\sqrt{5}+2}\)
2) \(\dfrac{4}{1-\sqrt{3}}+\dfrac{\sqrt{3}-1}{\sqrt{3}+1}\)
3) \(\dfrac{\sqrt{2}-1}{\sqrt{2}+1}-\dfrac{3-\sqrt{2}}{3+\sqrt{2}}\)
4) \(\dfrac{6}{1-\sqrt{3}}-\dfrac{3\sqrt{3}-3}{\sqrt{3}+1}\)
5) \(\dfrac{\sqrt{5}+\sqrt{6}}{\sqrt{5}-\sqrt{6}}+\dfrac{\sqrt{6}-\sqrt{5}}{\sqrt{6}+\sqrt{5}}\)
Chứng minh rằng:
a) \(\frac{2^3-1}{2^3+1}.\frac{3^3-1}{3^3+1}...\frac{n^3-1}{n^3+1}>\frac{2}{3}\)
b) \(\frac{1}{1^4+4}+\frac{1}{3^4+4}+...+\frac{2n+1}{\left(2n+1\right)^4+4}< \frac{1}{4}\)
Rút gọn phân thức sau : \(\frac{2^3-1}{2^3+1}.\frac{3^3-1}{3^3+1}.\frac{4^3-1}{4^3+1}......\frac{n^3-1}{n^3+1}\) (với n\(\in\) N, n>3)
Cho dãy số 1/1 ; 1/2 ; 2/1 ; 1/3 ; 2/2 ; 3/1 ; 1/4 ; 2/3 ; 3/2 ; 4/1 ; 1/5 ; 2/4 ; 3/3 ; 4/2 ; 5/1 ; 1/6 ; 2/5 ; 3/4...
Tìm số thứ 2013
Tính:
1) \(\dfrac{1}{1+\sqrt{5}}+\dfrac{1}{\sqrt{5}-1}\)
2) \(\dfrac{1}{\sqrt{5}+\sqrt{3}}-\dfrac{1}{\sqrt{5}-\sqrt{3}}\)
3) \(\dfrac{1}{\sqrt{2}-\sqrt{3}}-\dfrac{1}{\sqrt{3}+\sqrt{2}}\)
4) \(\dfrac{1}{3+\sqrt{5}}+\dfrac{1}{\sqrt{5}-3}\)
5) \(\dfrac{1}{\sqrt{2}-\sqrt{6}}-\dfrac{1}{\sqrt{6}+\sqrt{2}}\)
LM CHI TIẾT GIÚP MK NHÉ
A. 1/3^2 + 1/4^2 1/5^2 + ... + 1/100^2 < 4/9
B . 1/(-2)^3 + 1/(-3)^3 + 1/(-4)^ 3 + ... 1/(-100)^3 > 3/(-2)^3
Ai giải hộ mình cái
cho 3 số thực dưỡng, y, z thỏa mản xyz=1. tìm GTLN của
A=1/(x^3 +y^3 +1) + 1/(y^3 + z^3 + 1) + 1/(z^3 + x^3 +1)
