Các bạn giúp mk nhé mk đang cần gấp ^_^

mình nghĩ là : 1/2 < 2/3 < 3/4 < 4/5 < 5/6 < 6/7 < 7/8 < 8/9 < 9/10

Thankyou bạn

4/5 > 3/7

11/15 < 12/6

-3/7 < -4/9

-5/8 < 4/-7

Bài làm

-)

\(-\frac{9}{4}=\frac{-9\cdot3}{4\cdot3}=\frac{-27}{12}\)

\(\frac{1}{3}=\frac{1\cdot4}{3\cdot4}=\frac{4}{12}\)

Vì -27 < 4 => -27/12 < 4/12

Do đó: \(-\frac{9}{4}< \frac{1}{3}\)

-)

\(-\frac{8}{3}=\frac{-8\cdot7}{3\cdot7}=\frac{-56}{21}\)

\(\frac{4}{-7}=\frac{4\cdot3}{-7\cdot3}=\frac{12}{-21}=\frac{12\cdot-1}{-21\cdot-1}=\frac{-12}{21}\)

Vì -56 < -12 => -56/21 < -12/21

Do đó: \(-\frac{8}{3}< \frac{4}{-7}\)

-)

\(\frac{9}{-5}=\frac{9\cdot2}{-5\cdot2}=\frac{18}{-10}=\frac{18\cdot-1}{-10\cdot-1}=\frac{-18}{10}\)

\(\frac{7}{-10}=\frac{7\cdot-1}{-10\cdot-1}=\frac{-7}{10}\)

Vì -18 < -7 => -18/10 < -7/10

Do đó: \(\frac{9}{-5}< \frac{7}{-10}\)

a -9/4 < 1/3

b -8/3< 4/-7

c 9/-5 < 7/-10 

ht

a) Ta có:

\(\dfrac{8}{9}=\dfrac{40}{45}\)

\(\dfrac{7}{5}=\dfrac{63}{45}\)

\(\Rightarrow\dfrac{8}{9}< \dfrac{6}{5}\left(\dfrac{40}{45}< \dfrac{63}{45}\right)\)

b) Ta có:

\(\dfrac{3}{4}=\dfrac{15}{20}\)

\(\dfrac{4}{5}=\dfrac{16}{20}\)

\(\Rightarrow\dfrac{3}{4}< \dfrac{4}{5}\left(\dfrac{15}{20}< \dfrac{16}{20}\right)\)

Câu `5`

`a)` Ta có:

`8/9 < 1 ; 7/5>1`

Vì: `8/9 < 1 < 7/5` nên `8/9 < 7/5`

`b)3/4= 15/20`

`4/5 = 16/20`

Vì: `15/20 < 16/20` nên `3/4<4/5`

Giống thứ tự bạn đã đánh luôn

\(\dfrac{13}{17}< \dfrac{30}{34}\)                                        \(\dfrac{9}{8}>\dfrac{5}{7}\) 

 \(\dfrac{15}{7}< \dfrac{8}{3}\)                                        \(\dfrac{5}{7}< \dfrac{7}{5}\)                     

\(\dfrac{16}{20}=\dfrac{4}{5}\)

1. A - B = 40+ 3/8 + 7/8² + 5/8³ + 32/8^{5 -} (24/8² + 40+ 5/8² + 40/8⁴ + 5/8^{4 )}

⁼ 40.8⁵/8⁵ + 3.8⁴/8⁵ + 7.8³/8⁵ + 5.8²/8⁵ + 32/8⁵ - 24.8³/8⁵ - 40.8⁵/8⁵ - 5.8³/8⁵ - 40.8/8⁵ - 5.8/8⁵

⁼ 40.8⁵/8⁵ + 24.8³/8⁵ + 7.8³/8⁵ + 5.8²/8⁵ + 32/8⁵ - 24.8³/8⁵ - 40.8⁵/8⁵ - 5.8³/8⁵ - 40.8/8⁵ - 5.8/8⁵

⁼ 7.8³/8⁵ + 5.8²/8⁵ + 32/8⁵ - 5.8³/8⁵ - 40.8/8⁵ - 5.8/8⁵

⁼ 7.8³/8⁵ + 5.8²/8⁵ -8/8⁵ - 5.8³/8⁵ - 40.8/8⁵

= 2.8³/8⁵ + 5.8²/8⁵ - 40.8/8⁵ - 8/8⁵

= 2.8³/8⁵ + 40.8/8⁵ - 40.8/8⁵ - 8/8⁵

= 2.8³/8⁵  - 8/8⁵ > 0 

Vay A > B

ai so sanh C va D di ma duoc thi minh se tink cho