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12 tháng 8 2021

các bạn giúp mình bài 4 nhé. cảm ơn các bn nhiều

12 tháng 8 2021

các bạn ơi giúp mình với ạ 

13 tháng 8 2021

mn ơi cần gấpppppp

T^T

13 tháng 8 2021

She is nice ?                                                   the children are in their class now

They don't are students.                                Are they workers ? No , they aren't

He is fine today                                                các câu còn lại thì tự làm !!

My brother doesn't is a doctor         

 

b: Đặt \(\dfrac{a}{b}=\dfrac{c}{d}=k\)

\(\Leftrightarrow\left\{{}\begin{matrix}a=bk\\c=dk\end{matrix}\right.\)

Ta có: \(\dfrac{\left(a+c\right)^2}{\left(b+d\right)^2}\)

\(=\dfrac{\left(bk+dk\right)^2}{\left(b+d\right)^2}\)

\(=k^2\)(1)

Ta có: \(\dfrac{a^2-c^2}{b^2-d^2}\)

\(=\dfrac{\left(bk\right)^2-\left(dk\right)^2}{b^2-d^2}\)

\(=k^2\left(2\right)\)

Từ (1) và (2) suy ra \(\dfrac{\left(a+c\right)^2}{\left(b+d\right)^2}=\dfrac{a^2-c^2}{b^2-d^2}\)

Đặt \(\dfrac{a}{b}=\dfrac{c}{d}=k\)

\(\Leftrightarrow\left\{{}\begin{matrix}a=bk\\c=dk\end{matrix}\right.\)

Ta có: \(\dfrac{4a+3c}{4b+3d}=\dfrac{4bk+3dk}{4b+3d}=k\)

\(\dfrac{4a-3c}{4b-3d}=\dfrac{4bk-3dk}{4b-3d}=k\)

Do đó: \(\dfrac{4a+3c}{4b+3d}=\dfrac{4a-3c}{4b-3d}\)

30 tháng 12 2021

? Tiếng gì đây , giống tiếng Trung quá ta

30 tháng 12 2021

;-; :)?? 😞🤘🏻 :v

10 tháng 7 2021

ex 4.

1 seeing

2 to pay

3 sneezing

4 to clean up

5 to work

6 cutting

7 to iron - ironing

8 driving

9 to have

10 to invite

11 being

12 to find

13 holding - drinking

14 to repair

15 explaining

ex 5.

2. Pamela continued dancing for an hour.

3. I'd rather sit in the front row.

4. Richard expects to do well.

5. What do you intend to do for the summer?

6. I hate clearing up my room.

7. Helen agreed to go to the party with me.

8. My boss refused to let me leave early.

9. I really look forward to hearing from you soon.

10. What do you want to do this evening?

11. The manager promised to speak to you about this.

12. Fiona succeeded in persuading her father to change his mind.

13. Where do you feel like going this evening?

14. The detective happened to discover the secret.

15. It was very late, but she went on tidying up the kitchen.

ex6.

1. The room will be cleaned today.

2. The car might be stolen.

3. That tree had to be cut down.

4. The old houses are going to be demolished.

5. The picture can't be restored.

6. An appointment must be made in advance.

7. I don't want to be made a fool.

8. The garden has to be looked after.

9. He wants to be served.

10. He is going to be interviewed next week.

31 tháng 10 2021

11 My sister walks to school

12 The bank is near the post office

13 Our garden has many flowers

14 Ba doesn't like Math

15 Nam doesn't live in the countryside

31 tháng 10 2021

11. My sister walks to school
12. The bank is near the post office
13. Our garden has many flowers
14. Ba doesn't like Math best
15. Nam doesn't live in the country

uses crt;

var st:array[1..100]of string;

a,b,c:array[1..100]of real;

i,n:integer;

max:real;

begin

clrscr;

readln(n);

for i:=1 to n do readln(st[i],a[i],b[i],c[i]);

max=(a[1]+b[1]+c[1])/3;

for i:=1 to n do 

if (max<(a[i]+b[i]+c[i])/3) then max:=(a[i]+b[i]+c[i])/3;

writeln(max:4:2);

readln;

end.