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28 tháng 5 2015

so sorry . I dont understand

 

28 tháng 5 2015

Giải quyết từng tập thể dục bằng cách sử dụng tỷ lệ vàng\(\left(1+\sqrt{5}\right)\) : 2.
Tỉ lệ giữa chiều cao: chiều rộng của một vườn hoa bằng với tỷ lệ vàng. Chiều rộng của khu vườn là 14 feat. Tìm chiều dài của khu vườn. Thể hiện câu trả lời của bạn trong hình thức đơn giản nhất và triệt để ở bàn chân

14 tháng 12 2016

Cho một hình chữ nhật mà chiều rộng của nó là một nửa  chiều dài. Tỉ lệ giữa chu vi của hình chữ nhật với chiều rộng của nó là ?

Bài giải:

Gọi chiều rộng là: R; chiều dài là D; Chu vi là CV của hình chữ nhật

Theo đề bài ta có: R=1/2D. Suy ra D=2R                                      

    Mà chu vị hình chữ nhật là: CV = (D+R)x2.                              

Tỉ lệ giữa chu vi của hình chữ nhật với chiều rộng là: CV:R  = (2R +R)x2 : R

                                                                                       = 3Rx2:R =6

   Đáp án: 6                                                                                    

câu 1: A rectangle has a length of 60cm and a width of 30cm. It is cut into 2 indentical squares, 2 identical rectangles and a shaded small square. Find the area of the shaded square. Find the area of the shaded square. câu 2.The number of ordered pairs (x; y) where x, y ∈ N* such that x2y2 - 2(x + y) is perfect square is .......... câu 3.Let ABCD be the square with the side length 56cm. If E and F lie on CD, C respectively such that CF = 14cm and EAF = 45o then CE = ........cm. câu...
Đọc tiếp

câu 1: A rectangle has a length of 60cm and a width of 30cm. It is cut into 2 indentical squares, 2 identical rectangles and a shaded small square. Find the area of the shaded square.
Find the area of the shaded square.
Đề thi violympic toán tiếng anh lớp 8 vòng 10
câu 2.The number of ordered pairs (x; y) where x, y ∈ N* such that x2y2 - 2(x + y) is perfect square is ..........

câu 3.Let ABCD be the square with the side length 56cm. If E and F lie on CD, C respectively such that CF = 14cm and EAF = 45o then CE = ........cm.

câu 4.

Given P(x) = (x2 - 1/2 x - 1/2)1008
If P(x) = a2016x2016 + a2015x2015 + ..... + a1x + a0
then the value of the sum a0 + a2 + a4 + .... + a2014 is ...........

Write your answer by decimal in simplest form câu 5.Let ABC be an isoceles triangle (AB = AC) and its area is 501cm2. BD is the internal bisector of the angle ABC (D ∈ AC), E is a point on the opposite ray of CA such that CE = CB. I is a point on BC such that CI = 1/2 BI. The line EI meets AB at K, BD meets KC at H. Find the area of the triangle AHC. câu 6. all roots of the polynomial P(x) = x2 + 5x - 1 are also roots of the polynomial Q(x) = x3 + ax2 + bx + c then the value of a + b + 6c is ............ câu 7.Suppose that the polynomial f(x) = x5 - x4 - 4x3 + 2x2 + 4x + 1 has 5 solutions x1; x2; x3; x4; x5. The other polynomial k(x) = x2 - 4.
Find the value of P = k(x1) x k(x2) x k(x3) x k(x4) x k(x5) câu 8.The smallest value of Đề thi violympic toán tiếng anh lớp 8 vòng 10 is ............. câu 9.Let ABCD be a trapezoid with bases AB, CD and O be the intersection of AC and BD. If the areas of triangle OAB, triangle OCD are 16cm2, 40cm2respectively and M is the midpoint of BD, then the area of the triangle AMD is .........cm2. câu 10.Bottle A contains 15% syrup. Bottle B contains 40% syrup. When these 2 bottles of syrup are mixed, the syrup content is 30% and the total volume is 600ml. How much syrup is in the bottle A at first? câu 11.Let ABCD.A'B'C'D' be a cube with AC' = √3cm. Find the total surface area of this cube. câu 12.Let ABC be a triangle with AB = 3cm, AC = 7cm. The internal bisector of the angle BAC intersects BC at D. The line passing through D and parallel to AC cuts AB at E. Find the measure of DE. câu 12.Given two numbers x, y such that (4y2 - 12y + 25)(4x2 + 6x + 4) = 28
The ratio of y to x is ........ câu 13.Mr.Joseph drives car from A to B at a constant speed. If the speed of the car is increased by 20%, it takes him one hour less than the usual time. If he drives at the constant speed for the first 100km before increasing the speed by 30%, it also takes him one hour less than the usual. The distance of AB is ..........km. câu 14.A triangle ABC has  = 120o and the bisector AD (D ∈ BC). If AB = 40cm, AD = 30cm, then AC = ..... cm. câu 15.As shown in the figure, the length of BE is .............
Đề thi violympic toán tiếng anh lớp 8 vòng 10 câu 16.

Let f(x) the polynomial given by f(x) = (1 + 2x + 3x2 + 4x3 + 5x4 + 84x5)
Suppose that f(x) = ao + a1x + a2x2 + ..... + ..... + a50x50.
The value of T = a1 + a2 + .... + a50 is .........

  • a. 9910 - 1
  • b. 9910
  • c. 10010
  • d. 10010 - 1
  • câu 17.Find the area of the trapezoid ABCD, BC // AD, AB = CD = 5cm, BC = 10cm, AD = 16cm.
    The area of the trapezoid ABCD is .........cm2.
  • câu 18.Find the least possible value of A = 4x2 - 3x + 1/4x + 2015, where x varies in the set of positive real numbers. The least possible value of A is
  • câu 19.
0
Giúp mình làm các câu hỏi này nha: (càng nhiều càng tốt!)1. Tiffany and Ryan deposit some amount in a joint bank account such that total balance remains 500. If  amount deposited by Tiffany and Ryan are plotted as a linear graph on xy plane, find the area between this graph and the coordinate axis.2.A group of workers is paving a road. If they pave 200m of the road a day, they will need 3 more days. to finish the work. If they pave 240m of the road a day, they will finish the work...
Đọc tiếp

Giúp mình làm các câu hỏi này nha: (càng nhiều càng tốt!)

1. Tiffany and Ryan deposit some amount in a joint bank account such that total balance remains 500. If  amount deposited by Tiffany and Ryan are plotted as a linear graph on xy plane, find the area between this graph and the coordinate axis.

2.A group of workers is paving a road. If they pave 200m of the road a day, they will need 3 more days. to finish the work. If they pave 240m of the road a day, they will finish the work 2 days in advance. How long is the road, in meter?

3. Mrs. Darlie has a silver ring, a golden ring and a diamond ring. She put them on her left hand. Each ring can be on any of the five fingers. When there are two or three rings on the same finger, if the order in which they are put is different, that couunt as a different way. How many different ways for Lea to put these rings?

4. Let P(x) be a polynomial with degree 3 such that P(1)=3, P(2)=3, P(3)=7, P(4)=21. Find the value of P(5).

1

4. Call that polynomial P (x) = ax3 + bx2 + cx + d

We have P(1)=a+b+c+d=3   (1)

P(2)=8a+4b+2c+d=3   (2)

P(3)=27a+9b+3c+d  =7       (3) 

P(4)=64a+16b+4c+d     =21    (4)

From (1) and  (2) =>  7a+3b+c=0

From (1) and  (4)  => 63a+15b+3c=18

=> 12b+6c=-18  => 2b+c=-3

From (1) and  (3) =>26a+8b+2c=4=> 13a+4b+c=2

=> 13a+2b=5

It is possible

Giúp mình làm các câu hỏi này nha: (càng nhiều càng tốt!)1. Tiffany and Ryan deposit some amount in a joint bank account such that total balance remains 500. If  amount deposited by Tiffany and Ryan are plotted as a linear graph on xy plane, find the area between this graph and the coordinate axis.2.A group of workers is paving a road. If they pave 200m of the road a day, they will need 3 more days. to finish the work. If they pave 240m of the road a day, they will finish the work...
Đọc tiếp

Giúp mình làm các câu hỏi này nha: (càng nhiều càng tốt!)

1. Tiffany and Ryan deposit some amount in a joint bank account such that total balance remains 500. If  amount deposited by Tiffany and Ryan are plotted as a linear graph on xy plane, find the area between this graph and the coordinate axis.

2.A group of workers is paving a road. If they pave 200m of the road a day, they will need 3 more days. to finish the work. If they pave 240m of the road a day, they will finish the work 2 days in advance. How long is the road, in meter?

3. Mrs. Darlie has a silver ring, a golden ring and a diamond ring. She put them on her left hand. Each ring can be on any of the five fingers. When there are two or three rings on the same finger, if the order in which they are put is different, that couunt as a different way. How many different ways for Lea to put these rings?

4. Let P(x) be a polynomial with degree 3 such that P(1)=3, P(2)=3, P(3)=7, P(4)=21. Find the value of P(5).

2
1. Tiffany và Ryan gửi một số tiền vào tài khoản ngân hàng chung sao cho tổng số dư còn lại 500. Nếu số tiền được gửi bởi Tiffany và Ryan được vẽ dưới dạng biểu đồ tuyến tính trên mặt phẳng xy, hãy tìm khu vực giữa biểu đồ này và trục tọa độ. 2.Một nhóm công nhân đang mở đường. Nếu họ mở 200m đường mỗi ngày, họ sẽ cần thêm 3 ngày nữa. để hoàn thành công việc. Nếu họ mở 240m đường mỗi ngày, họ sẽ hoàn thành công việc trước 2 ngày. Bao lâu là đường, tính bằng mét? 3. Bà Darlie có một chiếc nhẫn bạc, một chiếc nhẫn vàng và một chiếc nhẫn kim cương. Cô đặt chúng lên tay trái. Mỗi chiếc nhẫn có thể nằm trên bất kỳ ngón tay nào trong năm ngón tay. Khi có hai hoặc ba chiếc nhẫn trên cùng một ngón tay, nếu thứ tự chúng được đặt khác nhau, thì đó là một cách khác nhau. Có bao nhiêu cách khác nhau để Lea đặt những chiếc nhẫn này? 4. Đặt P (x) là một đa thức có bậc 3 sao cho P (1) = 3, P (2) = 3, P (3) = 7, P (4) = 21. Tìm giá trị của P (5).
21 tháng 6 2019

#)Góp ý :

Mấy câu như thế này thì bạn nên lên Discuss with Math You - MathYou hỏi nhé ^^

Vì web này chuyên cho học sinh giải toán tiếng anh nên lên đây hỏi sẽ tiện hơn

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions from 1 to 10. Reading to oneself is a modern activity which was almost unknown to the scholars of the classical and medieval worlds, while during the fifteenth century the term "reading" undoubtedly meant reading aloud. Only during the nineteenth century did silent reading become commonplace. One should be wary, however, of assuming that silent reading came...
Đọc tiếp

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions from 1 to 10.

Reading to oneself is a modern activity which was almost unknown to the scholars of the classical and medieval worlds, while during the fifteenth century the term "reading" undoubtedly meant reading aloud. Only during the nineteenth century did silent reading become commonplace.

One should be wary, however, of assuming that silent reading came about simply because reading aloud was a distraction to others. Examinations of factors related to the historical development of silent reading have revealed that it became the usual mode of reading for most adults mainly because the tasks themselves changed in character.

The last century saw a steady gradual increase in literacy and thus in the number of readers. As the number of readers increased, the number of potential listeners declined and thus there was some reduction in the need to read aloud. As reading for the benefit of listeners grew less common, so came the flourishing of reading as a private activity in such public places as libraries, railway carriages and offices, where reading aloud would cause distraction to other readers.

Towards the end of the century, there was still considerable argument over whether books should be used for information or treated respectfully and over whether the reading of materials such as newspapers was in some way mentally weakening. Indeed, this argument remains with us still in education. However, whatever its virtues, the old shared literacy culture had gone and was replaced by the printed mass media on the one hand and by books and periodicals for a specialised readership on the other.

By the end of the twentieth century, students were being recommended to adopt attitudes to books and to use reading skills which were inappropriate, if not impossible, for the oral reader. The social, cultural and technological changes in the century had greatly altered what the term "reading" implied.

Question 1: Reading aloud was more common in the medieval world because:

A. people relied on reading for entertainment

B. silent reading had not been discovered

C. there were few places available for private reading

D. few people could read to themselves

Question 2: The word "commonplace" in the first paragraph mostly means:

A. for everybody's use B. most preferable

C. attracting attention D. widely used

Question 3: The development of silent reading during the last century indicated

A. an increase in the average age of readers

B. an increase in the number of books

C. a change in the nature of reading

D. a change in the status of literate people

Question 4: Silent reading, especially in public places, flourished mainly because of:

A. the decreasing need to read aloud

B. the development of libraries

C. the increase in literacy

D. the decreasing number of listeners

Question 5 It can be inferred that the emergence of the mass media and specialized reading materials was an indication of .

A. a decline of standards of literacy

B. a change in the readers' interest

C. an alteration in educationalists ’attitudes

D. an improvement of printing techniques.

Question 6: The phrase "a specialized readership" in paragraph 4 mostly means:

A. a requirement for readers in a particular area of knowledge

B. a limited number of readers in a particular area of knowledge

C. a reading volume for particular professionals

D. a status for readers specialized in mass media

Question 7: The phrase “oral reader" in the last paragraph mostly means a person who:

A. is good at public speaking

B. practices reading to an audience

C. takes part in an audition

D. is interested in spoken language

Question 8: All of the following might be the factors that affected the continuation of the old shared literacy culture EXCEPT .

A. the inappropriate reading skills B. the specialized readership

C. the diversity of reading materials D. the printed mass media

Question 9: Which of the following statements is NOT TRUE according to the passage?

A. Reading aloud was more common in the past than it is today.

B. Not all printed mass media was appropriate for reading aloud.

C. The decline of reading aloud was wholly due to its distracting effect.

D. The change in reading habits was partly due to the social, cultural and technological changes.

Question 10: The writer of this passage is attempting to .

A. explain how reading habits have developed

B. change people's attitudes to reading

C. show how reading methods have improved

D. encourage the growth of reading.

3

Bạn đăng trên box Anh nhé,Bạn đang đăng trên box Toán đấy

2 tháng 10 2019

Tham khảo

Câu 1. Đáp án D few people could read to themselves

Thông tin ở đầu đoạn 1:”Reading to………….reading aloud”. (Đọc thầm 1 mình là 1 hoạt động hiện đại mà hầu như không hề được biết đến đối với các học giả thời cổ điển và thời trung cổ,trong khi vào thế kỷ 15,nói đến đọc nghĩa là đọc lớn tiếng.)

Câu 2. Đáp án D widely used

Định nghĩa của commonplace: được sử dung rộng rãi,phổ biến thông dụng

Câu 3. Đáp án C a change in the nature of reading

Thông tin ở 2 đoạn 2:”examination of factors………….in character”. (Sự khỏa sát các yếu tố liên quan đến sự phát triển có tính lịch sử của việc đọc thầm đã trở thành lối đọc thông dụng đối với đa số người lớn vì bản thân việc đọc đã thay đổi bản chất.)

Câu 4. Đáp án C the increase in literacy

Thông tin ở đầu đoạn 3:”The lát century saw…………………to read aloud”: (Thế kỷ vừa qua chứng kiến 1 sự gia tăng, số người đọc tiềm năng giảm bớt và do vậy nhu cầu đọc lớn tiếng cũng giảm đi.)

Câu 5. Đáp án A a decline of standards of literacy

Thông tin ở cuối đoạn 4:”However,………..on the other”: Tuy nhiên dù lợi ích của việc đọc là gì đi nữa,thì cái nền văn hóa chia sẻ tri thức của ngày xưa cũng đã biến mất và bị thay thế bởi 1 nền báo chí và 1 bên là sách vở và các ấn phẩm định kỳ dành cho các độc giả chuyên ngành

Câu 6. Đáp án B a limited number of readers in a particular area of knowledge

Số đọc giả có giới hạn chuyên về 1 ngành kiến thức riêng biệt

Câu 7. Đáp án B practises reading to an audience (Đọc cho 1 số thính giả nghe)
Câu 8. Đáp án A the inappropriate reading skills (Kỹ năng đọc không phù hợp)
Câu 9. Đáp án C

The decline of reading aloud was wholly due to its distracting effect. Sự suy giảm việc đọc lớn tiếng la do tác dụng làm phiền người khác của nó

Câu 10. Đáp án A explain how reading habits have developed

Tác giả đã cố giải thích thói quen đọc đã thay đổi như thế nào

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 32 to 41. Plants and animals will find it difficult to escape from or adjust to the effects of global warming. Scientists have already observed shifts in the lifecycles of many plants and animals, such as flowers blooming earlier and birds hatching earlier in the spring. Many species have begun shifting where they live or their annual migration...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 32 to 41.

Plants and animals will find it difficult to escape from or adjust to the effects of global warming. Scientists have already observed shifts in the lifecycles of many plants and animals, such as flowers blooming earlier and birds hatching earlier in the spring. Many species have begun shifting where they live or their annual migration patterns due to warmer temperatures.
With further warming, animals will tend to migrate to ward the poles and up mountainsides toward higher elevations. Plants will also attempt to shift their ranges, seeking new areas as old habitats grow too warm. In many places, however, human development will prevent these shifts. Species that find cities or farmland blocking their way north or south may become extinct. Species living in unique ecosystems, such as those found in polar and mountaintop regions, are especially at risk because migration to new habitats is not possible. For example, polar bears and marine mammals in the Arctic are already threatened by dwindling sea ice but have nowhere farther north to go.
Projecting species extinction due to global warming is extremely difficult. Some scientists have estimated that 20 to 50 percent of species could be committed to extinction with 2 to 3 Celsius degrees of further warming. The rate of warming, not just the magnitude, is extremely important for plants and animals. Some species and even entire ecosystems, such as certain types of forest, may not be able to adjust quickly enough and may disappear.
Ocean ecosystems, especially fragile ones like coral reefs, will also be affected by global warming. Warmer ocean temperatures can cause coral to “bleach”, a state which if prolonged will lead to the death of the coral. Scientists estimate that even 1 Celsius degree of additional warming could lead to widespread bleaching and death of coral reefs around the world. Also, increasing carbon dioxide in the atmosphere enters the ocean and increases the acidity of ocean waters. This acidification further stresses ocean ecosystems.

From "Global Warming" by Michael Mastrandrea an d Stephen H. Schneider

Scientists have observed that warmer temperatures in the spring cause flowers to ______.

  • A. bloom earlier
  • B. die instantly
  • C. become lighter
  • D. lose color
  • Câu 2:

    According to paragraph 2, when their habitats grow warmer, animals tend to move ______.

    • A. toward the North Pole and down mountainsides toward lower elevations
    • B. toward the poles and up mountainsides toward higher elevations
    • C. south-eastwards and down mountainsides toward lower elevations
    • D. north-westwards and up mountainsides toward higher elevations
  • Câu 3:

    The pronoun “those” in paragraph 2 refers to ______.

    • A. areas
    • B. habitats
    • C. species
    • D. ecosystems
  • Câu 4:

    The phrase “dwindling sea ice” in paragraph 2 refers to ______.

    • A. the cold ice in the Arctic
    • B. the violent Arctic Ocean
    • C. the melting ice in the Arctic
    • D. the frozen water in the Arctic
  • Câu 5:

    It is mentioned in the passage that if the global temperature rose by 2 or 3 Celsius degrees, ______.

    • A. half of the earth’s surface would be flooded
    • B. water supply would decrease by 50 percent
    • C. the sea level would rise by 20 centimeters
    • D. 20 to 50 percent of species could become extinct
  • Câu 6:

    According to the passage, if some species are not able to adjust quickly to warmer temperatures, ______.

    • A. they will certainly need water
    • B. they can begin to develop
    • C. they may be endangered
    • D. they move to tropical forests
  • Câu 7:

    The word “fragile” in paragraph 4 most probably means ______.

    • A. pretty hard
    • B. easily damaged
    • C. rather strong
    • D. very large
  • Câu 8:

    The bleaching of coral reefs as mentioned in paragraph 4 indicates ______.

    • A. the slow death of coral reefs
    • B. the blooming phase of sea weeds
    • C. the quick growth of marine mammals
    • D. the water absorption of coral reefs
  • Câu 9:

    The level of acidity in the ocean is increased by ______.

    • A. the loss of acidity in the atmosphere around the earth
    • B. the decrease of acidity of the pole waters
    • C. the extinction of species in coastal areas
    • D. the rising amount of carbon dioxide entering the ocean
  • Câu 10:

    What does the passage mainly discuss?

    • A. Global warming and possible solutions
    • B. Global warming and species migration
    • C. Influence of climate changes on human lifestyles
    • D. Effects of global warming on animals and plants
2
2 tháng 10 2019

Ummm bạn đăng sang bên tiếng anh nhé :>

2 tháng 10 2019

Tham khảo ở câu hỏi này nè:

Câu hỏi của Tên Của Tôi - Toán lớp 9 | Học trực tuyến

30 tháng 8 2020

e chỉ biết mỗi đề bài thôi chứ bài này khó lắm

Đề bài:

Ann và Bob có một số lượng lớn đồ ngọt mà họ đồng ý chia sẻ theo các quy tắc sau. Ann sẽ lấy một viên ngọt, sau đó Bob sẽ lấy hai viên kẹo và sau đó thay phiên nhau, mỗi người lấy một viên ngọt hơn những gì người kia vừa lấy. Khi số kẹo còn lại ít hơn số kẹo sẽ lấy ở lượt đó thì người cuối cùng lấy hết số kẹo còn lại. Trước sự ngạc nhiên của họ, khi họ ăn xong, họ đều có số kẹo như nhau

Họ quyết định thực hiện chia lại lần nữa, nhưng lần này, trước tiên, họ chia kẹo thành hai đống bằng nhau và sau đó lặp lại quy trình trên với mỗi đống. Ann đi đầu tiên cả hai lần. Họ vẫn kết thúc với cùng một số lượng kẹo mỗi loại.

Số lượng đồ ngọt tối đa ít hơn 1000 mà họ có thể bắt đầu bằng là bao nhiêu?

9 tháng 2 2016

viết tiếng việt ra đi duyetj nha