so sánh 13/27 và 7/5
2007/2005 và 2005/2003
1997/2003 và 1995/2001
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(TC:\)
\(\dfrac{2007}{2005}=\dfrac{2005+2}{2005}=1+\dfrac{2}{2005}\)
\(\dfrac{2005}{2003}=\dfrac{2003+2}{2003}=1+\dfrac{2}{2003}\)
\(\text{Khi đó :}\)
\(\dfrac{2}{2003}>\dfrac{2}{2005}\) \(\)
\(\Rightarrow\dfrac{2005}{2003}>\dfrac{2007}{2005}\)
2001/2001<2005/2003 vì 2001/2001=1 mà 2005/2003 >1 Vậy 2001/2001<2005/2003
Có \(\frac{2001}{2001}=1=\frac{2003}{2003}\)
Mà \(\frac{2003}{2003}< \frac{2005}{2003}\)
=>\(\frac{2001}{2001}< \frac{2005}{2003}\)
\(\frac{2005}{2003}-1=\frac{2}{2003}\)
\(\frac{2003}{2001}-1=\frac{2}{2001}\)
Vì \(\frac{2}{2003}\frac{2003}{2001}\)
\(A=\frac{2002}{2001}+\frac{2003}{2002}+\frac{2004}{2003}+\frac{2005}{2004}+\frac{2006}{2005}+\frac{2007}{2006}+\frac{2008}{2007}+\frac{2009}{2008}>\frac{2001}{2001}+\frac{2002}{2002}+\frac{2003}{2003}+\frac{2004}{2004}+\frac{2005}{2005}+\frac{2006}{2006}+\frac{2007}{2007}+\frac{2008}{2008}\)
\(A=\frac{2002}{2001}+\frac{2003}{2002}+\frac{2004}{2003}+\frac{2005}{2004}+\frac{2006}{2005}+\frac{2007}{2006}+\frac{2008}{2007}+\frac{2009}{2008}>1+1+1+1+1+1+1+1\)\(A=\frac{2002}{2001}+\frac{2003}{2002}+\frac{2004}{2003}+\frac{2005}{2004}+\frac{2006}{2005}+\frac{2007}{2006}+\frac{2008}{2007}+\frac{2009}{2008}>8\)
\(A>8\)
B = \(\frac{2001}{2002}+\frac{2002}{2003}\)
có: \(\frac{2000}{2001}>\frac{2000}{2001}+2002\)
\(\frac{2001}{2002}>\frac{2001}{2001}+2002\)
Vậy A>B
13/27<7/5
2007/2005<2005/2003
1997/2003>1995/2001