2007/2008 x 1/209 + 2007/2008 : 2009/2008+1/2008
Những câu hỏi liên quan
tính:
C=2007/2008 x 1/2009 + 2007/2008 : 2009/2008 + 1/2008
So sánh: x = 2006/2007 - 2007/2008 + 2008/2009 - 2009/2010.
y = - 1/(2006 × 2007) - 1/(2007 × 2008).
Ta có:
\(x=\dfrac{2006}{2007}-\dfrac{2007}{2008}+\dfrac{2008}{2009}-\dfrac{2009}{2010}\)
\(=\dfrac{2006.2008-2007^2}{2007.2008}+\dfrac{2008.2010-2009^2}{2009.2010}\)
\(=\dfrac{2006.2007+2006-2007^2}{2007.2008}+\dfrac{2008.2009+2008-2009^2}{2009.2010}\)
\(=\dfrac{2007\left(2006-2007\right)+2006}{2007.2008}+\dfrac{2009\left(2008-2009\right)+2008}{2009.2010}\)
\(=\dfrac{-1}{2007.2008}+\dfrac{-1}{2008.2010}< \dfrac{-1}{2006.2007}+\dfrac{1}{2007.2008}\)
\(\Rightarrow x< y\)
Vậy x < y
Đúng 0
Bình luận (3)
So sánh
bài 1 :A= 2006/2007-2007/2008+2008/2009-2009/2010
B= -1/2006*2007-1/2008*2009
bài 2: C= 2006/2007+2007/2008+2008/2009+2009/2006 với 4
Câu 1: So sánh các số hữu tỉ:
A = 2006/2007 - 2007/2008 + 2008/2009 - 2009/2010 với B = -1/2006 x 2007 - (-1)/2007 x 2008
2007/2008.1/2009 + 2007/2008 +2009/2008+1/2008
2. So sánh A và B:
A= 2006/2007 - 2007/2008 + 2008/2009 - 2009/2010
B=-1/2006*2007 - 1/2008*2009
so sánh 2008 với tổng 2009 số hạng sau\(s=\frac{2008+2007}{2009+2008}+\frac{^{2008^2+2007^2}}{2009^2+2008^2}+.....+\frac{2008^{2009}+2007^{2009}}{2009^{2009}+2008^{2009}}\)
So sánh :A=2008^2008 +1 /2008^2009 B =2008^2007 +1 /2008^2008+1
A=\(\dfrac{2008^{2008}+1}{2008^{2009}+1}\) B=\(\dfrac{2008^{2007}+1}{2008^{2008}+1}\)
