rồi câu hỏi đou =)

bình thường mà

Ừ

cũng đúng

44 diet

45 medical

46 skillful

47 may

48 much

49 either

50 taking

Ex1

0 Lan is in grade 7

1 She likes learning E

2 She always wants to improve her E

3 Last week, she bought an English-Vietnamese dictionary

4 She often uses it for reading

5 Now she speaks E well 

EX2

0 Viet is my friend

1 He likes playing sports very much

2 In his free time, he often plays soccer with his friends

3 He likes watching soccer matches on TV

4 He also likes fishing

5 On the weekends he often goes fishing with his father or brother

Xin chân thành cảm ơn đã giải các bài tiếng anh khó cho mình 

( 125 x 0,75 + 125 x 25% ) x ( 9 x 11 - 0,9 x100 - 0,9 x10)

=( 125 x 0,75 + 125 x 25% ) x          0

=          0

xuống

bạn chụp rõ đề bài để mn giúp nhé!

bài 10 : 94dm

bài 11 : 5 giờ kém 15

a: Để A là số nguyên thì \(2n-3\in\left\{1;-1\right\}\)

hay \(n\in\left\{2;1\right\}\)

\(a,A=\dfrac{-3\left(2n-3\right)-8}{2n-3}=-3-\dfrac{8}{2n-3}\in Z\\ \Leftrightarrow2n-3\inƯ\left(8\right)=\left\{-1;1\right\}\left(2n-3\text{ lẻ}\right)\\ \Leftrightarrow n\in\left\{1;2\right\}\)

\(b,\dfrac{ab}{a+2b}=\dfrac{3}{2}\Leftrightarrow\dfrac{a+2b}{ab}=\dfrac{1}{b}+\dfrac{2}{a}=\dfrac{2}{3}\\ \dfrac{bc}{b+2c}=\dfrac{4}{3}\Leftrightarrow\dfrac{b+2c}{bc}=\dfrac{1}{c}+\dfrac{2}{b}=\dfrac{3}{4}\\ \dfrac{ca}{c+2a}=3\Leftrightarrow\dfrac{c+2a}{ca}=\dfrac{1}{a}+\dfrac{2}{c}=\dfrac{1}{3}\)

Cộng vế theo vế \(\Leftrightarrow\dfrac{3}{a}+\dfrac{3}{b}+\dfrac{3}{c}=\dfrac{2}{3}+\dfrac{3}{4}+\dfrac{1}{3}=\dfrac{7}{4}\)

\(\Leftrightarrow3\left(\dfrac{1}{a}+\dfrac{1}{b}+\dfrac{1}{c}\right)=\dfrac{7}{4}\\ \Leftrightarrow\dfrac{ab+bc+ca}{abc}=\dfrac{7}{12}\\ \Leftrightarrow T=\dfrac{abc}{ab+bc+ca}=\dfrac{12}{7}\)