Ta có:

\(A=\frac{2003\times2004-1}{2003\times2004}=\frac{2003\times2004}{2003\times2004}-\frac{1}{2003\times2004}=1-\frac{1}{2003\times2004}\)

\(B=\frac{2004\times2005-1}{2004\times2005}=\frac{2004\times2005}{2004\times2005}-\frac{1}{2004\times2005}=1-\frac{1}{2004\times2005}\)

Vì \(\frac{1}{2003\times2004}>\frac{1}{2004\times2005}\Rightarrow A< B\)

cảm ơn bạn nhiều

\(A=\frac{1}{2\times4}+\frac{1}{4\times6}+\frac{1}{6\times8}+...+\frac{1}{2012\times2014}\)

\(=\frac{1}{2}\times(\frac{2}{2\times4}+\frac{2}{4\times6}+\frac{2}{6\times8}+...+\frac{2}{2012\times2014})\)

\(=\frac{1}{2}\times(\frac{1}{2}-\frac{1}{4}+\frac{1}{4}-\frac{1}{6}+\frac{1}{6}-\frac{1}{8}+...+\frac{1}{2012}-\frac{1}{2014})\)

\(=\frac{1}{2}\times(\frac{1}{2}-\frac{1}{2014})\)

\(=\frac{1}{2}\times(\frac{1007}{2014}-\frac{1}{2014})\)

\(=\frac{1}{2}\times\frac{503}{1007}\)

\(=\frac{503}{2014}\)

Ta có ; \(\frac{1}{2}=\frac{1007}{2014}\)

Vậy A bé hơn B

Chúc bạn học tốt

1

1/5<7/6

3/7<4/2

2

15<45

21>3

5=4+1

1)

a) Do 5/5 = 1

=> 1/5 < 1

Do 6/6 = 1

=> 7/6 > 1

=> 7/6 > 1/5

b) Như trên ta có : 3/7 < 1

 4/2 > 1

=> 4/2 > 3/7

2)

a ) <

b) >

c) =

Làm giúp mik rồi mik tik cho ạ

Bài 5:

Đặt \(G=\overline{ab,c}\)

=>\(G\times10=\overline{abc}\)

\(\overline{abc}+\overline{ab,c}=502,7\)

=>G+10G=502,7
=>11G=502,7

=>G=45,7

=>a=4; b=5; c=7

Bài 4: Đặt \(G=\overline{a,b}\)

=>\(10\times G=\overline{ab}\)

Sửa đề: \(\overline{ab}+\overline{a,b}=16,5_{\overline{}}\)

=>G+10G=16,5

=>11G=16,5

=>G=1,5

=>\(\overline{a,b}=1,5\)

=>a=1; b=5

Bài 2:

a: \(\overline{0,abc}\times100=6,2\times10+7,5\)

=>\(\overline{ab,c}=62+7,5=69,5\)

=>a=6; b=9; c=5

b: \(\overline{0,abc}\times100=8,1\times10+4,4\)

=>\(\overline{ab,c}=81+4,4=85,4\)

=>a=8; b=5; c=4

Bài 1:

a: \(\overline{a,87}+\overline{2,b2}=a+0,87+2+0,1b+0,02=a+0,1b+2,89\)

\(\overline{a,b}+2,89=a+0,1b+2,89\)

Do đó: \(\overline{a,87}+\overline{2,b2}=\overline{a,b}+2,89\)

b: \(\overline{a,bc}+20,04+28,63=a+0,1b+0,01c+48,67\)

\(\overline{3a,81}+\overline{4,b5}+\overline{13,9c}=30,81+a+4,05+0,01b+13,9+0,01c\)

=a+0,01b+0,01c+48,76>a+0,1b+0,01c+48,67

=>\(\overline{3a,81}+\overline{4,b5}+\overline{13,9c}>\overline{a,bc}+20,04+28,63\)

c: M=20,09x20,13

=(20,11-0,02)x(20,11+0,02)

=20,11x20,11-0,02x0,02

=N-0,02x0,02

=>M<N

a) ta có: \(A=\frac{2017.2018-1}{2017.2018}=\frac{2017.2018}{2017.2018}-\frac{1}{2017.2018}=1-\frac{1}{2017.2018}\)

\(B=\frac{2018.2019-1}{2018.2019}=1-\frac{1}{2018.2019}\)

\(\Rightarrow\frac{1}{2017.2018}>\frac{1}{2018.2019}\)

\(\Rightarrow1-\frac{1}{2017.2018}< 1-\frac{1}{2018.2019}\)

=> A < B

a)A= 2017*2018/2017*2018-1/2017*2018=1-1/2017*2018

    B = 2018*2019/2018*2019-1/2018*2019=1-1/2018*2019

vì 1/2017*2018>1/2018*2019=> A<B

b)

Ta có:

\(A=\frac{2017\cdot2018-1}{2017\cdot2018-2}\)

\(A=\frac{2017\cdot2018-2+1}{2017\cdot2018-2}\)

\(A=\frac{2017\cdot2018-2}{2017\cdot2018-2}+\frac{1}{2017\cdot2018-2}\)

\(A=1+\frac{1}{2017\cdot2018-2}\)

Ta có phân số trung gian là 1. Ta có:
\(A>1\) ; \(B< 1\)

\(\Rightarrow A>1>B\)

\(\Rightarrow A>B\)

Vậy A>B
Chúc em học tốt!

\(\Rightarrow\text{❤️✔✨♕✨✔️❤ }\Leftarrow\)

\(\text{Ta có :}\)

\(A=\frac{2017\cdot2018-1}{2017\cdot2018-2}=\frac{4070305}{4070304}=1\frac{1}{4070304}\)

\(B=\frac{2017}{2018}\)

\(\text{Vì : }1\frac{1}{4070304}>1\text{ mà }\frac{2017}{2018}< 1\text{ nên }1\frac{1}{4070304}>\frac{2017}{2018}\)

\(\Rightarrow A>B\)

\(B=\frac{2003+2004}{2004+2005}=\frac{2003}{2004+2005}+\frac{2004}{2004+2005}\)

Ta có: \(\frac{2003}{2004}>\frac{2003}{2004+2005}\)

          \(\frac{2004}{2005}>\frac{2004}{2004+2005}\)

\(\frac{2003}{2004}+\frac{2004}{2005}>\frac{2003+2004}{2004+2005}\)

\(A>B\)

Vậy A>B

đáp án là A>B

chúc bn hok tốt!