Câu1 bạn ko nêu rõ đầu bài cho lắm

Câu2 

Số phần tử là :

(60-6):2+1=28

Tổng là : 

(60+6)×28:2=924

Câu2 bạn ko nêu kết quả

dễ quá nhỉ

Bài này chỉ vận dụng phân tích đa thức thành nhân tử thôi

Có: \(\left(x-y\right)^2+\left(y-z\right)^2+\left(z-x\right)^2=6xyz\)

\(\Leftrightarrow2\left(x^2+y^2+z^2-xy-yz-xz\right)=6xyz\)

\(\Leftrightarrow x^2+y^2+z^2-xy-yz-xz=3xyz\)

\(\Leftrightarrow\left(x+y+z\right)\left(x^2+y^2+z^2-xy-yz-xz\right)=3xyz\left(x+y+z\right)\)

\(\Leftrightarrow x^3+y^3+z^3-3xyz=3xyz\left(x+y+z\right)\)

\(\Leftrightarrow x^2+y^3+z^3=3xyz\left(x+y+z+1\right)\)

Do đó: \(x^3+y^3+z^3+1=3xyz\left(x+y+z+1\right)+1⋮x+y+z+1\)

Suy ra: \(1⋮x+y+z+1\)

 \(\Rightarrow x+y+z+1=1\)( do \(x,y,z\ge0\Rightarrow x+y+z+1\ge1\))

\(\Leftrightarrow x=y=z=0\)

Vậy \(x=y=z=0\)

1:  Only with careful environmental planning can we protect the world in which we live.

D.  We can protect the world we live in only with careful environmental planning.

2:  You should take regular exercises instead of sitting in front of the television all day.

A.  Taking regular exercises is better than sitting in front of the television all day.

3:  It was not until after I got home that I realized I had not set the burglar alarm in the office.

C.  I didn’t turn the burglar alarm on before I left the office, but I only became aware of this after I'd arrived home.

4:  He did not remember the meeting. He went out for a coffee with his friends then.

D.  Not remembering the meeting, he went out for a coffee with his friends.

5:  They left their home early. They didn’t want to miss the first train.

C.  They left their home early so as not to miss the first train.

6:  I’m sure Luisa was very disappointed when she failed the exam

B.  Luisa must have been very disappointed when she failed the exam.

7.  “You had better see a doctor if the sore throat does not clear up.” she said to me.

D.  She suggested that I see a doctor if the sore throat did not clear up.

8:  Without her teacher’s advice, she would never have written such a good essay

C.  She wrote a good essay as her teacher gave her some advice.

9.  She tried very hard to pass the driving test. She could hardly pass it.

C.  No matter how hard she tried, she could hardly pass the driving test.

10. Mary loved her stuffed animal when she was young. She couldn’t sleep without it.

A. When Mary was young, she loved her stuffed animal so much that she couldn't sleep without it.

1:  Only with careful environmental planning can we protect the world in which we live.

A.  Careful environmental planning protects the world we live in.

B.  Planning the environment carefully, we can protect the world in which we live.

C.  Protecting the world we live in, we plan the environment carefully.

D.  We can protect the world we live in only with careful environmental planning.

2:  You should take regular exercises instead of sitting in front of the television all day.

A.  Taking regular exercises is better than sitting in front of the television all day.

B.  Sitting in front of the television all day helps you take regular exercises.

C.  Sitting in front of the television all day and taking exercises are advisable.

D.  Don’t take regular exercises, just sit in front of the television all day.

3:  It was not until after I got home that I realized I had not set the burglar alarm in the office.

A.  On the way home, I suddenly realized that I had forgotten to turn on the burglar alarm in the office.

B.  Fortunately, I realized that I hadn't set the burglar alarm just before I left for home; otherwise, I would have had to travel all the way back to the office.

C.  I didn’t turn the burglar alarm on before I left the office, but I only became aware of this after I'd arrived home.

D. I wish I had realized before I arrived home that I hadn't turned on the burglar alarm in the office, then it would have been easier to go and set it.

4:  He did not remember the meeting. He went out for a coffee with his friends then.

A.  Not remember the meeting, he went out for a coffee with his friends.

B.  Not to remember the meeting, he went out for a coffee with his friends.

C.  Not remembered the meeting, he went out for a coffee with his friends.

D.  Not remembering the meeting, he went out for a coffee with his friends.

5:  They left their home early. They didn’t want to miss the first train.

A.  They left their home early so as to not miss the first train.

B.  They left their home early for fear that they wouldn’t miss the first train.

C.  They left their home early so as not to miss the first train.

D.  They left their home early in order that not to miss the first train.

6:  I’m sure Luisa was very disappointed when she failed the exam

A.  Luisa must be very disappointed when she failed the exam.

B.  Luisa must have been very disappointed when she failed the exam.

C. Luisa may be very disappointed when she failed the exam.

D. Luisa could have been very disappointed when she failed the exam.

1:  Only with careful environmental planning can we protect the world in which we live.

D.  We can protect the world we live in only with careful environmental planning.

2:  You should take regular exercises instead of sitting in front of the television all day.

A.  Taking regular exercises is better than sitting in front of the television all day.

3:  It was not until after I got home that I realized I had not set the burglar alarm in the office.

C.  I didn’t turn the burglar alarm on before I left the office, but I only became aware of this after I'd arrived home.

4:  He did not remember the meeting. He went out for a coffee with his friends then.

D.  Not remembering the meeting, he went out for a coffee with his friends.

5:  They left their home early. They didn’t want to miss the first train.

 

C.  They left their home early so as not to miss the first train.

D.  They left their home early in order that not to miss the first train.

6:  I’m sure Luisa was very disappointed when she failed the exam

B.  Luisa must have been very disappointed when she failed the exam.

 

Số sách tam khảo mà thư viện có là :

( 2433 + 1173 ) : 2 = 1803 ( quyển )

Đáp số : 1803 quyển sách

Bài giải :

  Số sách tham khảo thư viện mới mua là :

         (2433 + 1173) : 2 = 1803 ( quyển )

                  Đ/S:...

so sach tham khảo trường vừa mua là:2433-1173=1260                                                                                                                                   đáp số:1260 

Hic...đã thi rùi!!!!!

 

Mình chắc chắn đề của trường mình khác trường bạn, vì mình ở khác tỉnh bạn, mình không lo Văn lắm nhưng mình lại lo môn Toán và Anh Văn cơ, nếu có thì bạn giúp mình nhé

khac de truong mk qua nhieu

 

Dàn bài:

Mở bài: Giới thiệu về những kỉ niệm của em.

Thân bài: Kể chi tiết.

Kỉ niệm 1:  Em được đi du lịch cùng gia đình đến Hạ Long.

Tâm trạng háo hức trước khi đi.Quang cảnh trên đường( cây cối,, bầu trời, biển, bãi cát…)Kỉ niệm diễn ra như thế nào? tâm trạng lúc đó (hân hoan, phấn khởi, vui vẻ…)Tâm trạng khi phải về (tiêc nuôi, mong ước, gắn kêt gia đình)

Kỉ niệm 2: Gặp lại bạn cũ.

Hoàn cảnh khi gặp lại bạn ( thời gian, địa điểm)Diễn biến của cuộc gặp gỡ ( ôn lại kỉ niệm xưa, kể về gia đình và bạn bè, trao đổi địa chỉ…)Suy nghĩ khi chia tay bạn ( vui vì muốn gặp lại, muốn gặp lâu hơn)

Kỉ niệm 3:  Đi lao động cùng chị gái.

 Không khí trong trước buổi lao động ( không khi tâp bật, náo nhiệt, mọi người tay cầm xô, cầm xẻng, cầm chổi, bàn tán)Bác trưởng thôn phân công nhiệm vụEm cùng mọi người làm việc hăng say, mọi người giúp đỡ nhau, mệt nhưng vui, hình ảnh mọi người lao động)Cảm nghĩ của em sau buổi lao động ( vui, cảm thấy có ý  nghĩa, thêm yêu đời hơn…)

Kết bài: Suy nghĩ của bản thân về kì nghỉ hè bổ ích

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Đây bn ạ ! Bạn có thể tham khảo bài này của mình. Mk tự làm nha! :)

Chúc bạn học tốt!

Bài văn của bạn đọc xong là muốn đến Nha Trang ngay :) ncl 1 từ để diễn tả : Hay Nguyễn Phương Linh