| |x - 2017 | + 1 | = 30

TH1: | x - 2017 | + 1 = -30

=> | x - 2017 | = - 31

=> x \(\in\varnothing\)

TH2: | x - 2017 | + 1 = 30

=> | x - 2017 | = 29

=> \(\left[{}\begin{matrix}x-2017=29\\x-2017=-29\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=2046\\x=1988\end{matrix}\right.\)

1. They said to us, " Must you go now?"

->.............................They asked if they might go now............................

2. Nam said to me, " Did you stay at home last night?"

->.....................Nam asked if I stayed at home last night....................................

3. He said to her, " you are my friend."

->.......................He said to her that she was his friend..................................

4. Johnny said to his father , " I don't know how to do this exercise."

->........................Johnny said to his father that he didn't know how to done the exercise.................................

5. The pupils said, " Teacher , give us better mark, please."

->.......................The pupils asked their teacher to give them better mark..................................

6. " What a dirty face you have !" Ann said to her son.

->........................Ann said to her son that what a dirty face her son had................................

7. " Who is coming in the excursion tomorrow?" She said

->.........................She asked who was coming in the excursion the next day ................................

8. " You have to take at least two bottles of water," Tam's father said.

->.......................Tam's father advised her to take at least two bottles of water..................................

9. " I will clean all the class windows," said Trung

->..........................Trung said he would clean all the class windows ...............................

10. " Help me to hang this picture, Ba" said Mai

->......................Mai told Ba to help her to hang this picture...................................

11. " My brother doesn't like eating sticky rice," sai Linh

->............................Linh said her brother didn't like eating sticky rice.............................

12. " Do you want to visit the Great Wall in China, Tam?" I said

->........................I asked Tam if she wanted to visit the Great Wall in China.................................

1) Ta có: x = -2 là nghiệm của f(x)

\(\Rightarrow f\left(-2\right)=\left(-2\right)^3+2.\left(-2\right)^2+a.\left(-2\right)+1=0\)

\(\Rightarrow f\left(-2\right)=-8+8-2a+1=0\)

\(\Rightarrow-2a+1=0\)

\(\Rightarrow-2a=-1\)

\(\Rightarrow a=0,5\)

2) Ta có: x = 1 là nghiệm của f (x)

\(\Rightarrow f\left(1\right)=1^2+a.1+b=0\)

\(\Rightarrow1+a+b=0\)

Ta có: x = 2 là một nghiệm của f (x)

\(\Rightarrow f\left(2\right)=2^2+a.2+b=0\)

\(\Rightarrow4+2a+b=0\)

\(\Rightarrow1+a+b=4+2a+b\)

\(\Rightarrow1+a+b-4-2a-b=0\)

\(\Rightarrow-3-a=0\Rightarrow a=-3\)

\(\Rightarrow1-3+b=0\Rightarrow b=2\)

1.i want to borrow....books..... from the library

2. Let's go to the post office to buy .......stamps..........

3. People couldn't sit down because there weren't......chairs.... in the hall

4. My little sister doesn't like this book because there aren't.......pictures ..... in it

5. Would you like to listen to .....music .......?

6. There isn't.....water...... here i am so thirsty

7. The baby is crying. He needs.......milks.......

8. I need to put .....petrol........... in my car. We are going to have a long journey

1. How are you?

2. And you?

3. Which class are you in?

4. Where is your classroom?

5. How many students are there in your class?

6. What time do you get up?

7. What time do you have breakfast?

8. What time do you go to school?

1. His school is in the country.

2. Thu's school is in the city.

3. There are forty classrooms in Nam's school.

4. There are four hundred students in the school.

5. Phong's school is small not big.

6. Is your school in the country?

Được rồi, nhưng sẽ không vẽ hình đâu vì đã làm dạng tương tự như thế này rồi -.-

Kẻ tia Cx // AB

\(\Rightarrow\widehat{BAC}+\widehat{ACx}=180^0\) ( 2 góc trong cùng phía)

\(\Rightarrow\widehat{ACx}=180^0-110^0=70^0\)

Theo hình vẽ, ta có:

\(\widehat{ACx}+\widehat{DCx}=110^0\)

\(\Rightarrow\widehat{DCx}=110^0-70^0=40^0\)

Ta lại thấy:

\(\widehat{DCx}+\widehat{CDE}=140^0+40^0=180^0\)

Mà 2 góc này ở vị trí 2 góc trong cùng phía

=> Cx // CD

Mà AB // Cx

=> AB // CD ( Quan hệ giữa đường vuông góc và 2 đường thẳng song song)

( Tự kết luận)

Hôm trước làm cho dạng tương tự thế này rồi. Không tự làm được à?

Ít nhất cũng phỉa cho thêm 1 góc nữa chứ