Công thức: must + V

I don't think he must go out now.

I don't think he must go out now.

5 to be

1. you must never come into this room without knocking first

2. I need to buy a small gift for my friend

3. The little boy was very interested in reading picture books

4. She intends to make a book report

5. He seems be very tired after work

6. It is impossible to meet Peter at this time

7. You needn't shout loudly

1 Ann facies doing DIY in her free time.

2 My father prefers not eating out.

3 Mr. Smith loves going shopping at weekend.

1 Ann fancies doing DIY in her free time

2 My father prefers not eating out

3 Mr Smith loves going shopping at weekend

   ∆ABC có BE là đường phân giác (gt)

  ∆ABC vuông tại A (gt)

⇒ BC² = AB² + AC² (Pythagore)

⇒ BC² - AB² = AC²

= (3 + 5)²

= 64

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

  Ta có:

BC² = AB² + AC² (Pythagore)

= 6² + 64

= 100

⇒ BC = 10

vì BE là đường phân giác của tam giác ABC nên ta có:

\(\dfrac{AE}{EC}=\dfrac{AB}{BC}=\dfrac{3}{5}\)

\(BC=\dfrac{5}{3}AB\)

áp dụng định lý pythagore vào tam giác ABC ta được:

\(AC^2=AB^2+BC^2\)

tổng độ dài đoạn AC là: 3 + 5 = 8

\(AB^2+BC^2=8^2\\ AB^2+\left(\dfrac{5}{3}AB\right)^2=64\\ AB^2+\dfrac{25}{9}AB^2=64\\ AB^2\cdot\left(1+\dfrac{25}{9}\right)=64\\ AB^2\cdot\dfrac{34}{9}=64\\ AB^2=64:\dfrac{34}{9}=64\cdot\dfrac{9}{34}\\ AB^2=\dfrac{576}{34}\\ AB=\sqrt{\dfrac{576}{34}}\text{≈}4,11\)

độ dài đoạn BC là:

BC² = AC² - AB²

BC² = 64 - 16,8921

BC² = 47,1079

BC = \(\sqrt{47,1079}\) ≈ 6,86

VẬY AB = 4,11; BC  =6,86

Đa thức $2x^4-21x^2+1$ không phân tích thành nhân tử bạn nhé.

1 to know

2 to meet

3 will tell

4 has just gone

5 has already known

6 to do

7 read

8 has just left

9 learn

#\(yGLinh\)

1. They ought ( know ) ..to know.. all the regulations in this school

2. It's very happy ( meet ) ..to meet. them again

3.I am sure they ( tell ) ..will tell. us about themselves soon

4. Nam isn't here. He ( just go ) .has just gone.. out for a walk

5. He (already know ) ..has already known. this regulation

6. Of us is ready ( do ) ..to do. the work

7. Have you ever ( read ) ...read. the story

8. Our teacher ( just leave ) ..has just left. the school

9. Pupils must ( learn) ..learn. their lessons before coming to class

Dưới đây là các câu hoàn chỉnh với các từ đã cho:

1. All of them have ready to give a book report. -> All of them are ready to give a book report.

2. We are much interested in English. -> We are very much interested in English.

3. Ask when he made the cake. -> Ask him when he made the cake.

4. Jane has never seen an elephant before. -> Jane has never seen an elephant before.

5. Enjoy books in spare time. -> I enjoy reading books in my spare time.

/s/: stops, arts, laughs, rocks

/iz/: quizzes, fixes, watches

/z/: friends, prefers

/ɪz/: quizzes, fixes, watches

/s/: stops, arts, laughs, rocks

/z/: friends, prefers