Bn ơi, bn lên ban hoi nhu ri vao trang khac. Là đc.

            Hok giỏi nha

\(ac=-\dfrac{1}{2}< 0\Rightarrow\) pt luôn có 2 nghiệm phân biệt trái dấu

Do \(x_1< x_2\Rightarrow\left\{{}\begin{matrix}x_1< 0\\x_2>0\\\end{matrix}\right.\)

\(\Rightarrow\left\{{}\begin{matrix}\left|x_1\right|=-x_1\\\left|x_2\right|=x_2\end{matrix}\right.\)

Đồng thời theo Viet: \(x_1+x_2=m\)

Ta có:

\(\left|x_2\right|-\left|x_1\right|=2021\)

\(\Leftrightarrow x_2-\left(-x_1\right)=2021\)

\(\Leftrightarrow x_1+x_2=2021\)

\(\Leftrightarrow m=2021\)

1 heavier => heaviest

2 best => the best

3 thin => thinner

4 happiest => happier

5 the oldest => older

6 sweeter => sweetest

7 cheapest => cheaper

Heavier → heavy

best → the best

thin → thinner

happiest → happier

the oldest → older

sweeter → sweetest

cheapest → cheaper

1 heavier☛heavy

2 best☛the best

3 thin☛thinner

4 happiest☛more happy

5 the oldest☛older

Refer:

Fill in an appropriate word in each blank.

Kipling was the first writer (1) was expressed the faith and national pride. He was (2) born in Bombay India (3) in 1865 and was taken (4) to England to (5) be educated at the (6) age of 6. But at the age of 17 he returned (7) to India and became a journalist. (8) by this time he (9) was a great amount of prose and portry. After wards he returned to England and travelled in Japan and America. He received the 1907 Nobel (10) prize for literature and died in 1936 while he was working on his autbiographical notes.

who - born - in - to - be - age - to - by - was - prize

1 If there were a library in my neighborhood, I could borrow books

2 If I had much free time, I could come to your party

3 If she were a bird, she could fly anywhere

4 Ì you don't study hard, you will fail the test

5 The castle was haunted so we were so scared

6 Despite the bad weather, the football match went on

7 Before she worked in this company, she had been married

8 Because of the dangerous acid rain, the leaves of many plants are damaged

9 Unless you try your best, the result will not be good

10 Because of the heavy rain, the match was cancelled

11 I haven't been to Bang Kok before

12 I have learnt English for 10 years

13 After having done some exercise, Kathy had a shower

14 The last time we talked to each other was 2 weeks ago

5 đc ko?

là sao ko hiểu lắm

a. \(R=\dfrac{R1\left(R2+R3\right)}{R1+R2+R3}=\dfrac{6\left(2+4\right)}{6+2+4}=3\Omega\)

b. \(U1=U23=U=IR=2.3=6V\)(R1//R23)

\(I23=I2=I3=U23:R23=6:\left(2+4\right)=1A\left(R2ntR3\right)\)

\(\left\{{}\begin{matrix}U2=I2.R2=1.2=2V\\U3=I3.R3=1.4=4V\end{matrix}\right.\)

Gọi số cần tìm là a

Theo bài ra: (a + 4) chia hết cho 6, 7 và 9

=> (a + 4) thuộc BC(6; 7; 9)

Mà BCNN(6; 7; 9) = 126

=> (a + 4) thuộc B(126) = {0; 126; 252; ...}

=> a thuộc {-4; 122; 248;...}

Vì a là số tự nhiên nhỏ nhất => a là 122