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22 tháng 9 2016

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

22 tháng 9 2016

dễ quá nhỉ

31 tháng 3 2019

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 \(x=y=z=0\)

Dạng bài tiếp theo xuất hiện trong đề thi tốt nghiệp THPT môn Tiếng Anh của các em đó chính là dạng tìm câu đồng nghĩa. Chúng ta cùng thử sức với 10 câu hỏi được lấy từ đề thi thử của các trường THPT Chuyên nhé! 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...
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Dạng bài tiếp theo xuất hiện trong đề thi tốt nghiệp THPT môn Tiếng Anh của các em đó chính là dạng tìm câu đồng nghĩa. Chúng ta cùng thử sức với 10 câu hỏi được lấy từ đề thi thử của các trường THPT Chuyên nhé!

 

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.

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

A.  She reminded me of seeing a doctor if the sore throat did not clear up.

B.  She ordered me to see a doctor if the sore throat did not clear up.

C.  She insisted that I see a doctor unless the sore throat did not clear up.

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

A.  Her teacher advised him and she didn't write a good essay.

B.  Her teacher didn't advise her and she didn't write a good essay.

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

D.  If her teacher didn't advise her, she wouldn't write such a good essay.

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

A.  Although she didn't try hard to pass the driving test, she could pass it.

B.  Despite being able to pass the driving test, she didn't pass it.

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

D.  She tried very hard, so she passed the driving test satisfactorily.

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.

B. When Mary was young, she loved her stuffed animal so as not to sleep without it.

C. When Mary was young, she loved her stuffed animal though she couldn't sleep without it.

D. As Mary couldn't sleep without her stuffed animal when Mary was young, she loved it.

9
15 tháng 4 2021

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.

15 tháng 4 2021

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.

18 tháng 8 2018

Số sách tam khảo mà thư viện có là :

( 2433 + 1173 ) : 2 = 1803 ( quyển )

Đáp số : 1803 quyển sách

18 tháng 8 2018

Bài giải :

  Số sách tham khảo thư viện mới mua là :

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

                  Đ/S:...

16 tháng 12 2016

Hic...đã thi rùi!!!!!khocroi

 

16 tháng 12 2016

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

6 tháng 9 2016

 

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 vụ
  • Em 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

6 tháng 9 2016

/hoi-dap/question/77784.html

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

Chúc bạn học tốt!