vì -2016/2017<1 và 1/10>1 => -2016/2017<1/10

Ta có 99/-100=-99/100>-1 nên 99/-100>1 và vì -102/101<-1 =>99/-100>-102/101

Ta có: 100+101/101+102

= 100/101+102 + 101/101+102

Vì 100/101>100/101+102

     101/102 > 101/101+102

=>100/101+101/102 > 100+101/101+102

cảm ơn bạn

Ta có :

\(\frac{102}{97}>1;\frac{99}{101}< 1\) nên \(\frac{102}{97}>\frac{99}{101}\)

Hok tốt

ta có: 102/97 > 99/97> 99/101

suy ra: 102/97> 99/101

ta có : -5.11 = -55 > 14. -4 = -56

suy ra -5/14 > -4/11

102/97 và 99/101

Quy đồng : 

\(\frac{102}{97}=\frac{102.101}{97.101}=\frac{10302}{9797}\) 

\(\frac{99}{101}=\frac{99.97}{101.97}=\frac{9603}{9797}\)

Ta thấy 10302>9603 nên 102/97 > 99/101

Bài dưới tương tự

\(\dfrac{97}{100}\)  và \(\dfrac{98}{99}\)

\(\dfrac{97}{100}=\dfrac{97\times99}{100\times99}=\dfrac{9603}{9900}\)

\(\dfrac{98}{99}=\dfrac{98\times100}{99\times100}=\dfrac{9800}{9900}\)

Vì: \(9603< 9800\)  nên => \(\dfrac{97}{100}< \dfrac{98}{99}\)

\(\dfrac{13}{17}\)  và \(\dfrac{131}{171}\)

\(\dfrac{13}{17}=\dfrac{13\times171}{17\times171}=\dfrac{2223}{2907}\)

\(\dfrac{131}{171}=\dfrac{131\times17}{171\times17}=\dfrac{2227}{2907}\)

Vì: \(2227>2223\)  nên: => \(\dfrac{13}{17}< \dfrac{131}{171}\)

\(\dfrac{51}{61}\)  và \(\dfrac{515}{616}\)

\(\dfrac{51}{61}=\dfrac{51\times616}{61\times616}=\dfrac{31416}{37576}\)

\(\dfrac{515}{616}=\dfrac{515\times61}{616\times61}=\dfrac{31415}{37576}\)

Vì: \(31416>31415\)  Nên => \(\dfrac{51}{61}>\dfrac{515}{616}\)

a/

$\frac{97}{100}< \frac{98}{100}< \frac{98}{99}$

c/

$\frac{131}{171}=1-\frac{40}{171}> 1-\frac{40}{170}=1-\frac{4}{17}=\frac{13}{17}$
d/

$\frac{51}{61}=1-\frac{10}{61}=1-\frac{100}{610}$

$\frac{515}{616}=1-\frac{101}{616}$

Xét hiệu:

$\frac{100}{610}-\frac{101}{616}=\frac{100.616-101.610}{610.616}$

$=\frac{100(610+6)-101.610}{610.616}$

$=\frac{600-610}{610.616}<0$

$\Rightarrow \frac{100}{610}< \frac{101}{616}$

$\Rightarrow 1-\frac{100}{610}> 1-\frac{101}{616}$

$\Rightarrow \frac{51}{61}> \frac{515}{616}$ 

7⁹⁹ + 7¹⁰⁰ + 7¹⁰¹ < 7¹⁰²

k mk nha ^_^

7^99+100+101=7³⁰⁰

Vì 300>102

Nên 7³⁰⁰>7¹⁰²

=> 7⁹⁹ + 7¹⁰⁰ + 7¹⁰¹ > 7102

sai hết òi

\(\dfrac{2}{15}=\dfrac{4}{30}>\dfrac{3}{20}\)

\(\Rightarrow\dfrac{-2}{15}=\dfrac{-4}{30}< \dfrac{3}{-20}\)

\(-\dfrac{2}{15}=-\dfrac{8}{60}\)

\(\dfrac{3}{-20}=-\dfrac{3}{20}=-\dfrac{9}{60}< -\dfrac{8}{60}\)

\(\Rightarrow\dfrac{3}{-20}< -\dfrac{2}{15}\)

\(\dfrac{-2}{15}\) và \(\dfrac{-3}{20}\) ( MC = 60 )

\(\dfrac{-2}{15}\) = \(\dfrac{-8}{60}\)

 \(\dfrac{-3}{20}\) = \(\dfrac{-9}{60}\)

Vì \(-8\) < \(-9\) nên \(\dfrac{-2}{15}\) < \(\dfrac{-3}{20}\) .

23,45<34,99;102,567>102,49

99,78>99,12;78,56=78,560

Bài 2,

3,45;4,3;5,6;5,9;102,609

Bài 1: 99,78 < 99,12  ; 78,56 > 78,560

Bài 2:

102,609 > 5,9 > 5,6 > 4,3 > 3,45

Bài 1:

23,45 < 34, 99        102,567  > 102,49

99,78 > 99,12         78,56 = 78,560

Cho mik làm lại bài 1 nha

Tất nhiên là \(\frac{102}{97}>\frac{99}{101}\) rùi vì \(\frac{102}{97}>1\)và\(\frac{99}{101}< 1\) nên \(\frac{102}{97}>\frac{99}{101}\)

\(\frac{102}{97}>1\\ \frac{99}{101}< 1\\ \Rightarrow\frac{102}{97}>1>\frac{99}{101}\)

Chúc bạn học tốt!