\(=\dfrac{2\left(3+2\sqrt{2}\right)+4}{3+2\sqrt{2}-3\sqrt{2}-3}\)
\(=\dfrac{10+4\sqrt{2}}{-\sqrt{2}}=-5\sqrt{2}+4\)
\(=\dfrac{2\left(3+2\sqrt{2}\right)+4}{3+2\sqrt{2}-3\sqrt{2}-3}\)
\(=\dfrac{10+4\sqrt{2}}{-\sqrt{2}}=-5\sqrt{2}+4\)
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 tổng \(S=\frac{1}{1^4+1^2+1}+\frac{2}{2^4+2^2+1}+\frac{3}{3^4+3^2+1}+...+\frac{2017}{2017^4+2017^2+1}\)
CMR : với mọi số nguyên dương n thì :
a, \(\frac{1}{3^2}+\frac{1}{5^2}+...+\frac{1}{\left(2n+1\right)^2}< \frac{1}{4}\)
b, \(\frac{1}{1^2+2^2}+\frac{1}{2^2+3^2}+...+\frac{1}{n^2+\left(n+1\right)^2}< \frac{1}{2}\)
c, \(\frac{1}{1^4+1^2+1}+\frac{1}{2^4+2^2+1}+\frac{3}{3^4+3^2+1}+...+\frac{n}{n^4+n^2+1}< \frac{1}{2}\)
Giải các phương trình sau:
1) 2 1 5 x 2) 2 1 5 x x
3) 3 1 2 x x 4) 3 2 2 x x
5) 2 1 5 x x 6) 3 2 x x
7) 2 3 2 1 x x 8) 2 1 4 1 0 x x 2
9) 2 5 4 3 1 1 2
3 2 3 1
x x
x x x x
10) 1 7 3 2
3 3 9
x x x
x x x
11) 5 296 2 1 3 1
16 4 4
x x
x x x
12)
2 4
1
2 1 2 1 2 1 2 1
x x
x x x x
13) 2 1 2 2
2 2
x
x x x x
14) 22 4
2 6 2 2 2 3
tinh C=can(1+1/2^2 +1/3^2)+ can(1+1/3^2 +1/4^2)+can(1+1/4^2 + 1/5^2)+...+can(1+1/2002^2 +1/2003^2)
Tính giá trị biểu thức:
\(\text{a) }\frac{1}{\sqrt{1}+\sqrt{2}}+\frac{1}{\sqrt{2}+\sqrt{3}}+\frac{1}{\sqrt{3}+\sqrt{4}}+\frac{1}{\sqrt{4}+\sqrt{5}}+...+\frac{1}{\sqrt{2010}+\sqrt{2011}}\)
\(\text{b) }\frac{1}{2\sqrt{1}+1\sqrt{2}}+\frac{1}{3\sqrt{2}+2\sqrt{3}}+\frac{1}{4\sqrt{3}+3\sqrt{4}}+...+\frac{1}{121\sqrt{120}+120\sqrt{121}}\)
\(\text{c) }\sqrt{1+\frac{1}{1^2}+\frac{1}{2^2}}+\sqrt{1+\frac{1}{2^2}+\frac{1}{3^2}}+\sqrt{1+\frac{1}{3^2}+\frac{1}{4^2}}+...\sqrt{+1+\frac{1}{2010^2}+\frac{1}{2011^2}}\)
Rút gọn biểu thức: \(\frac{1}{1^4+1^2+1}+\frac{2}{2^4+2^2+1}+\frac{3}{3^4+3^2+1}+...+\frac{2014}{2014^4+2014^2+1}\)
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
rut gon bieu thuc
1/(1^4+1^2+1)+2/(2^4+2^2+1)+3/(3^4+3^2+1)+...+2014/(2014^4+2014^2+2014)=...
{giup minh vs}
Rút gọn biểu thức: \(\frac{1}{1^4+1^2+1}+\frac{2}{2^4+2^2+1}+\frac{3}{3^4+3^2+1}+.....+\frac{2014}{2014^4+2014^2+1}\)