So sánh C và D:
\(C=\frac{2013^{2013}+1}{2013^{2014}+1}\) ; \(D=\frac{2013^{2012}+1}{2013^{2013}+1}\)
Tuyển Cộng tác viên Hoc24 nhiệm kì 26 tại đây: https://forms.gle/dK3zGK3LHFrgvTkJ6
so sánh
C=\(\frac{2013^{2013}+1}{2013^{2014}+1}\)
D=\(\frac{2013^{2012+1}}{2013^{2013}+1}\)
\(C=\frac{2013^{2013}+1}{2013^{2014}+1}\Rightarrow2013C=\frac{2013^{2014}+2013}{2013^{2014}+1}=\frac{2013^{2014}+1+2012}{2013^{2014}+1}=1+\frac{2012}{2013^{2014}+1}\)
\(D=\frac{2013^{2012}+1}{2013^{2013}+1}\Rightarrow2013D=\frac{2013^{2013}+2013}{2013^{2013}+1}=\frac{2013^{2013}+1+2012}{2013^{2013}+1}=1+\frac{2012}{2013^{2013}+1}\)
=>\(1+\frac{2012}{2013^{2014}+1}<1+\frac{2012}{2013^{2013}+1}\)
=>2013C<2013D
=>C<D
C = 20132013+ 1 / 20132014+1 < 20132013+1+2012 / 20132014+1+2012
= 20132013+2013 / 20132014+2013
= 2013(20132012+1) / 2013(20132013+1)
= 20132012+1 / 20132013+1 = D
=> C < D nhé!
Ai k mk mk k lại!!
Mình sẽ ko làm nữa vì bài của các bạn kia đúng rùi
nhưng mong các bạn !!!
So sánh C và D
C = 2013/2014 + 2014/2015
D = 2013+2014 / 2014+2015
So sánh C= \(\frac{2013}{2014}+\frac{2014}{2015}\)
và D=\(\frac{2013+2014}{2014+2015}\)
D\(\frac{2013}{2014+2015}+\frac{2014}{2014+2015}\)
Vì \(\frac{2013}{2014}>\frac{2013}{204+2015}\)
và \(\frac{2014}{2015}>\frac{2014}{2014+2015}\)
nên C>D
Ủng hộ mk nha
\(\frac{2013}{2014}+\frac{2014}{2015}=1,999...\)
\(\frac{2013+2014}{2014+2015}=4029\)
nen D>C
So sánh C và D , biết :
C = 2013/2014 + 2014/2015
D = \(\frac{2013+2014}{2014+2015}\)
Các bạn giải rõ ra hộ mk nha
D=2013+2014/ 2014+2015
D= 2013/2014+2015 + 2014/2014+2015
2013/2014+2015 < 2013/2014
2014/2014+2015 < 2014/2015
suy ra 2013/2014+2015 +2014/2014+2015 < 2013/2014+ 2014/2015
hay D < C ( ĐPCM)
XONG NHA BẠN !@!!!!!!!!!!!!!!!!!!!!chắc chắn đúng lun
So sánh 2 phân số: A= \(\frac{2014^{2013}+1}{2014^{2014}+1}\)và B= \(\frac{2014^{2012}+1}{2014^{2013}+1}\)
Gợi ý nhé: bạn hãy so sánh 2014A và 2014B rồi suy ngược lại A và B
Ta có:
2014A=20142014+ 2014/20142014+1=1+2013/20142014+1
2014B=20142013+2014/20142013+1=1+2013/20142013+1
vì 1+2013/20142014+1<1+2013/20142013+1 nên 10A < 10B
suy ra A<B
So sánh : C= 2013/2013+2014 + 2014/2014+2015 + 2015/2015+2016 ; D=2
\(C=\dfrac{2013}{2013}+2014+\dfrac{2014}{2014}+2015+\dfrac{2015}{2015}+2016\)
\(=1+2014+1+2015+1+2016\)
\(=6048>2\)
Vậy: \(C>D\)
So sánh \(C=\frac{2011^{2012}+1}{2011^{2013}+1}\)và \(D=\frac{2011^{2013}+1}{2011^{2014}+1}\)
D=\(\frac{2011^{2013}+1}{2011^{2014}+1}\)
<\(\frac{2011^{2013}+1+2010}{2011^{2014}+1+2010}\)
<\(\frac{2011^{2013}+2011}{2011^{2014}+2011}\)
<\(\frac{2011\left(2011^{2012}+1\right)}{2011\left(2011^{2013}+1\right)}\)
<\(\frac{2011^{2012}+1}{2011^{2013}+1}\)
<C
Vậy C>D
Cách 2:
Ta có: \(2011C=\frac{2011^{2013}+2011}{2011^{2013}+1}=1+\frac{2010}{2011^{2013}+1}\)
\(2011D=\frac{2011^{2014}+2011}{2011^{2014}+1}=1+\frac{2010}{2011^{2014}+1}\)
Mà \(\frac{2010}{2011^{2013}+1}>\frac{2010}{2011^{2014}+1}\Rightarrow1+\frac{2010}{2011^{2013}+1}>1+\frac{2010}{2011^{2014}+1}\)
\(\Rightarrow2011C>2011D\)
\(\Rightarrow C>D\)
Vậy C > D
so sánh giá trị A và B với
\(A=\frac{2013^{2014}+1}{2013^{2015}+1};\)\(B=\frac{2013^{2012}+1}{2013^{2013}+1}\)
1. So sánh M và N ( Ko Quy Đồng)
biết M = \(\frac{2012}{2013}+\frac{2013}{2014}+\frac{2014}{2015}\)và
N =\(\frac{2012+2013+2014}{2013+2014+2015}\)
( Giải rõ ràn nha) tớ tick cho
\(N=\frac{2012+2013+2014}{2013+2014+2015}=\frac{2012}{2013+2014+2015}+\frac{2013}{2013+2014+2015}+\frac{2014}{2013+2014+2015}\)
Ta thấy: \(\frac{2012}{2013}>\frac{2012}{2013+2014+2015}\)
\(\frac{2013}{2014}>\frac{2013}{2013+2014+2015}\)
\(\frac{2014}{2015}>\frac{2014}{2013+2014+2015}\)
\(\Rightarrow M=\frac{2012}{2013}+\frac{2013}{2014}+\frac{2014}{2015}>N=\frac{2012}{2013+2014+2015}+\frac{2013}{2013+2014+2015}+\frac{2014}{2013+2014+2015}\)
Vậy M>N