So sanh: A=2010+1 / 2010-1va B= 2010-1 / 2010-3
A=2010^2011+1/2010^2012+1
B=2010^2010+1/2010^2011+1
SO SANH A VA B
A = 20102011+1/ 20102012+1 < 20102011+1 + 2009 / 20102012+1+2009
= 20102011+2010/20102012+2010
=2010(2010^2010+1) / 2010(2010^2011+1)
= 2010^2010 + 1 / 2010^ 2011 +1 = B
=> A < B
Như vậy mới đúng nè
Ta có B=2010^2010 + 1/ 2010^2011 + 1 < 2010^2010+1+9/2010^2011+1+9=2010^2011+1/2010^2012+1
Vậy B<A
So sanh:
A = 20102011+1 phan 20102012+1 va B =20102010+1 phan 20102011+1
\(A=\frac{2010^{2011}+1+2009}{2010^{2012}+1+2009}=\frac{2010^{2011}+2010}{2010^{2012}+2010}=\frac{2010\left(2010^{2010}+1\right)}{2010\left(2010^{2011}+1\right)}\)\(=B\)
A=2010^2011+1/2010^2012+1B=2010^2010+1/2010^2011+1SO SANH A VA B.
Ta có:
\(A=\dfrac{2010^{2011}+1}{2010^{2012}+1}\)
\(A< \dfrac{2010^{2011}+1+2009}{2010^{2012}+1+2009}\)
\(A< \dfrac{2010^{2011}+2010}{2010^{2012}+2010}\)
\(A< \dfrac{2010\left(2010^{2010}+1\right)}{2010\left(2010^{2011}+1\right)}\)
\(A< \dfrac{2010^{2010}+1}{2010^{2011}+1}\)
Mà \(B=\dfrac{2010^{2010}+1}{2010^{2011}+1}\)
\(\Rightarrow A< B\)
So sanh A va B biet A=2010/2011+2011/2012+2012/2010 va B=1/3+1/4+1/5+....+1/17
so sanh (20102011+1)/(20102012+1)va( 20102010+1)/(20102011+1)
so sanh (20102011+1)/(20102012+1)va( 20102010+1)/(20102011+1)
so sanh 201050+1/201049+1 va 201049+1/201048+1
so sanh: A=2009^2009+1/2009^2010+1 và B=2009^2010-2/2009^2011-2
so sanh
A=2008/2009+2009/2010+2010+2011
B=2008+2009+2010/2009+2010+2011
Dễ thấy:
\(\frac{2008}{2009}>\frac{2008}{2009+2010+2011}\)
\(\frac{2009}{2010}>\frac{2009}{2009+2010+2011}\)
\(\frac{2010}{2011}>\frac{2010}{2009+2010+2011}\)
=>\(\frac{2008}{2009}+\frac{2009}{2010}+\frac{2010}{2011}>\frac{2008}{2009+2010+2011}+\frac{2009}{2009+2010+2011}+\frac{2010}{2009+2010+2011}\)
Hay \(\frac{2008}{2009}+\frac{2009}{2010}+\frac{2010}{2011}>\frac{2008+2009+2010}{2009+2010+2011}\)
Vậy A > B
so sanh 2^1+2^2+2^3+...+2^2010 va 2^2010+1