K
Khách

Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.

\(\frac{2016}{2017}< 1\)

\(\frac{2017}{2018}< 1\)

cho nên\(\frac{2016}{2017}+\frac{2017}{2018}< 1\)

4 tháng 5 2018

N = \(\frac{2016+2017}{2017+2018}=\frac{2016}{2017+2018}+\frac{2017}{2017+2018}\)

Ta có: \(\frac{2016}{2017}>\frac{2016}{2017+2018}\)

\(\frac{2017}{2016}>\frac{2017}{2017+2018}\)

Nên M > N

4 tháng 5 2018

Ta thấy : \(\frac{2016+2017}{2017+2018}\)=\(\frac{2016}{2017+2018}\)+\(\frac{2017}{2017+2018}\)

Vì : \(\frac{2016}{2017}\)>\(\frac{2016}{2017+2018}\)

\(\frac{2017}{2018}\)>\(\frac{2017}{2017+2018}\)

Cộng vế với vế ta được : \(\frac{2016}{2017}\)+\(\frac{2017}{2018}\)\(\frac{2016}{2017+2018}\)+\(\frac{2017}{2017+2018}\)

Hay M > N

Vậy M > N

Chúc bạn hok tốt !!

4 tháng 5 2018

\(A=\frac{2015}{2016}+\frac{2016}{2017}+\frac{2017}{2018}\)

\(B=\frac{2015+2016+2017}{2016+2017+2018}\)

\(B=\frac{2015}{2016+2017+2018}+\frac{2016}{2016+2017+2018}+\frac{2017}{2016+2017+2018}\)

Ta có:

\(\frac{2015}{2016}>\frac{2015}{2016+2017+2018}\)

\(\frac{2016}{2017}>\frac{2016}{2016+2017+2018}\)

\(\frac{2017}{2018}>\frac{2017}{2016+2017+2018}\)

Cộng vế theo vế, ta có:

\(\frac{2015}{2016}+\frac{2016}{2017}+\frac{2017}{2018}>\frac{2015}{2016+2017+2018}+\frac{2016}{2016+2017+2018}+\frac{2017}{2016+2017+2018}\)

\(hay\frac{2015}{2016}+\frac{2016}{2017}+\frac{2017}{2018}>\frac{2015+2016+2017}{2016+2017+2018}\)

\(\Rightarrow A>B\)

Vậy A >  B

28 tháng 5 2021
Bạn có nhầm không, tớ thấy cả hai đều giống nhau mà, Hai cái bằng nhau
2 tháng 7 2017

Vì phân số A\(=\frac{2016^{2017}+1}{2017^{2018}+1}< 1\) mà B\(=\frac{2017^{2018}+1}{2017^{2017}+1}>1\)

\(\Rightarrow\frac{2016^{2017}+1}{2017^{2018}+1}< 1< \frac{2017^{2018}+1}{2017^{2017}+1}\)

Vậy A<B

2 tháng 7 2017

a<1<b

=>A<b

1 tháng 5 2018

Bài 1:

ta có: \(B=\frac{12}{\left(2.4\right)^2}+\frac{20}{\left(4.6\right)^2}+...+\frac{388}{\left(96.98\right)^2}+\frac{396}{\left(98.100\right)^2}\)

\(B=\frac{4^2-2^2}{2^2.4^2}+\frac{6^2-4^2}{4^2.6^2}+...+\frac{98^2-96^2}{96^2.98^2}+\frac{100^2-98^2}{98^2.100^2}\)

\(B=\frac{1}{2^2}-\frac{1}{4^2}+\frac{1}{4^2}-\frac{1}{6^2}+...+\frac{1}{96^2}-\frac{1}{98^2}+\frac{1}{98^2}-\frac{1}{100^2}\)

\(B=\frac{1}{2^2}-\frac{1}{100^2}\)

\(B=\frac{1}{4}-\frac{1}{100^2}< \frac{1}{4}\)

\(\Rightarrow B< \frac{1}{4}\)

Bài 2:

ta có: \(B=\frac{2015+2016+2017}{2016+2017+2018}\)

\(B=\frac{2015}{2016+2017+2018}+\frac{2016}{2016+2017+2018}+\frac{2017}{2016+2017+2018}\)

mà \(\frac{2015}{2016}>\frac{2015}{2016+2017+2018}\)

\(\frac{2016}{2017}>\frac{2016}{2016+2017+2018}\)

\(\frac{2017}{2018}>\frac{2017}{2016+2017+2018}\)

\(\Rightarrow\frac{2015}{2016}+\frac{2016}{2017}+\frac{2017}{2018}>\frac{2015}{2016+2017+2018}+\frac{2016}{2016+2017+2018}+\frac{2017}{2016+2017+2018}\)

\(\Rightarrow A>B\)

Học tốt nhé bn !!

5 tháng 5 2018

=.....nha các bn. k mình nha

5 tháng 5 2018

Ta có : \(B=\frac{2015+2016+2017}{2016+2017+2018}\) \(=\frac{2015}{2016+2017+2018}+\frac{2016}{2016+2017+2018}+\frac{2017}{2016+2017+2018}\)

Mà \(\frac{2015}{2016}>\frac{2015}{2016+2017+2018}\)

       \(\frac{2016}{2017}>\frac{2016}{2016+2017+2018}\)

        \(\frac{2017}{2018}>\frac{2017}{2016+2017+2016}\)

Cộng vế theo vế, ta có : 

\(\frac{2015}{2016}+\frac{2016}{2017}+\frac{2017}{2018}>\frac{2015+2016+2017}{2016+2017+2018}\)

\(\Rightarrow A>B\)

25 tháng 4 2017

Do : \(\frac{2016}{2017}>\frac{2016}{2017+2018}\)

        \(\frac{2017}{2018}>\frac{2017}{2017+2018}\)

\(\Rightarrow\frac{2016}{2017}+\frac{2017}{2018}>\frac{2016}{2017+2018}+\frac{2017}{2017+2018}=\frac{2016+2017}{2017+2018}\)

Vậy : \(\frac{2016}{2017}+\frac{2017}{2018}>\frac{2016+2017}{2017+2018}\)

      

25 tháng 4 2017

Ta có:

\(\frac{2016}{2017}>\frac{2017}{2018}\Rightarrow A>\frac{2016}{2018}+\frac{2017}{2018}\Rightarrow A>\frac{2016+2017}{2018}\)

\(\frac{2016+2017}{2017+2018}=\frac{2016+2017}{4035}\)

Vì:\(\frac{2016+2017}{2018}>\frac{2016+2017}{4015}\)

Nên:\(\frac{2016}{2017}+\frac{2017}{2018}>\frac{2016+2017}{2017+2018}\)