a) ĐKXĐ:

x³ - 1 khác 0

x khác 1

b) A = (5x² + 5x + 5)/(x³ - 1)

= 5(x² + x + 1)/[(x - 1)(x² + x + 1)]

= 5/(x - 1)

Thay x = 7 vào A, ta được:

A = 5/(7 - 1)

= 5/6

1 send - will receive 

2 do - will improve

3 find - will give

4 will go - has

5 will go- gets

6 doesn't phone - will leave

7 don't study - won't pass

8 rains - won't have to

9 won't be able - watch

10 can't move - isn't

11 study - will pass

1 me 

2 too

3 done

doing

having

4 interested

5 as to

6 standing

when

7 helping

8 too

9 such

a

10 used

11 when

12 shouldn't

13 is - cost

Mình chưa thấy câu hỏi bạn ạ!

hong câu hỏi sao giải 

Áp dụng tính chất của dãy tỉ số bằng nhau, ta được

\(\dfrac{a}{3}=\dfrac{b}{4}=\dfrac{b-a}{4-3}=23\)

Do đó: a=69; b=92

Mình cảm ơn ạ

Chào em, em tham khảo nhé!

1. won't finish

2. had learnt

3. is

4. didn't rain

5. had gone

6. hadn't told

7. would understand

8. will throw

9. would be

10. will post

11. will go

12. is hitting

13. won't do

14. will make

15. will go

16. go

17. eat

18. was washed

19. will be built

20. was cleaned

Chúc em học tốt và có những trải nghiệm tuyệt vời tại hoc24.vn!

1 C => hers

2 B => will use

3 D => their

4 A => will be pedaling

5 A => travel

6 C => less

7 D => have they

8 D => than

9 A => worked

10 B => fewer

1 A

2 B

3 C

4 C

A 

B 

 C

C