Cho khi đó bằng:         

Hàm số nào sau đây không có tập xác định là khoảng ?                

Tập xác định của hàm số là.  

Tìm tập xác định D của hàm số .  

Cho biết tập xác định của hàm số  là một khoảng có độ dài (phân số tối giản). Tính giá trị m + n.   

Tập xác định của hàm số là ?         

Biểu thức xác định khi:         

Tìm tập xác định D của hàm số  .

Với giá trị nào của thì biểu thức xác định?  

Nếu và thì:  

Tập xác định của bất phương trình là:  

Tập xác định của hàm số  là  

Cho biểu thức . Tính tổng sau  

Tập xác định D của hàm số  là:

Tìm tập xác định D của hàm số y= .          

Gọi  là giá trị nhỏ nhất của  với  và . Hỏi có bao nhiêu giá trị của  để .  

Cho khi đó bằng:         

Tìm tất cả các giá trị thực của tham số  để hàm số  có tập xác định là

Tập xác định của hàm số là:         

Tìm tập xác định D của hàm số  .        

Tìm  để hàm số sau đồng biến trên R: .  

Tìm tập xác định  của hàm số .  

Trong các hàm số sau đây, hàm số nào có tập xác định ?  

Tìm tất cả các giá trị của tham số m sao cho hàm số có tập xác định .          

Tìm tập xác định của hàm số .  

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions:

The invention of the incandescent light bulb by Thomas A. Edison in 1879 created a demand for a cheap, readily available fuel with which to generate large amounts of electric power. Coal seem to fit the bill, and it fueled the earliest power stations (which were set up at the end of the nineteenth century by Edison himself). As more power plants were constructed throughout the country, the reliance on coal increased. Since the first World War, coal-fired power plants have accounted for about half of the electric produced in the United States each year. In 1986 such plants had a combined generating capacity of 289,000 megawatts and consumed 83 percent of the nearly 900 million tons of coal mined in the country that year. Given the uncertainty of the future growth of nuclear power and in the supply of oil and natural gas, coal-fired power plants could well provide up to 70 percent of the electric power in the United Stats by the end of the century.          

Yet, inspite of the fact that coal has long been a source of electricity and may remain one for many years (coal represents about 80 percent of the United States fossil-fuel reserves), it has actually never been the most desirable fossil fuel for power plants. Coal contain less energy per unit of weight than natural gas or oil; it is difficult to transport, and it is associated with a host of environmental issues, among them acid rain. Since the late 1960’s problems of emission control and waste disposal have sharply reduced the appeal of coal-fired power plants. The cost of ameliorating these environmental problems, along with the rising cost of building a facility as large and complex as a coal-fired power plant, has also made such plants less attractive from purely economic perspective.         

Change in the technological base of coal-fired power plants could restore their attractiveness, however. Whereas some of these changes are evoluntary and are intended mainly to increase the productivity of existing plants, completely new technologies for burning coal cleanly are also being developed.

Question: In the author’s opinion, the important of coal-generated electricity could increase in the future for which of the following reasons?         

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions:

The invention of the incandescent light bulb by Thomas A. Edison in 1879 created a demand for a cheap, readily available fuel with which to generate large amounts of electric power. Coal seem to fit the bill, and it fueled the earliest power stations (which were set up at the end of the nineteenth century by Edison himself). As more power plants were constructed throughout the country, the reliance on coal increased. Since the first World War, coal-fired power plants have accounted for about half of the electric produced in the United States each year. In 1986 such plants had a combined generating capacity of 289,000 megawatts and consumed 83 percent of the nearly 900 million tons of coal mined in the country that year. Given the uncertainty of the future growth of nuclear power and in the supply of oil and natural gas, coal-fired power plants could well provide up to 70 percent of the electric power in the United Stats by the end of the century.          

Yet, inspite of the fact that coal has long been a source of electricity and may remain one for many years (coal represents about 80 percent of the United States fossil-fuel reserves), it has actually never been the most desirable fossil fuel for power plants. Coal contain less energy per unit of weight than natural gas or oil; it is difficult to transport, and it is associated with a host of environmental issues, among them acid rain. Since the late 1960’s problems of emission control and waste disposal have sharply reduced the appeal of coal-fired power plants. The cost of ameliorating these environmental problems, along with the rising cost of building a facility as large and complex as a coal-fired power plant, has also made such plants less attractive from purely economic perspective.         

Change in the technological base of coal-fired power plants could restore their attractiveness, however. Whereas some of these changes are evoluntary and are intended mainly to increase the productivity of existing plants, completely new technologies for burning coal cleanly are also being developed.

Question: Acid rain is mentioned in the passage for which of the following reasons?         

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions:

The invention of the incandescent light bulb by Thomas A. Edison in 1879 created a demand for a cheap, readily available fuel with which to generate large amounts of electric power. Coal seem to fit the bill, and it fueled the earliest power stations (which were set up at the end of the nineteenth century by Edison himself). As more power plants were constructed throughout the country, the reliance on coal increased. Since the first World War, coal-fired power plants have accounted for about half of the electric produced in the United States each year. In 1986 such plants had a combined generating capacity of 289,000 megawatts and consumed 83 percent of the nearly 900 million tons of coal mined in the country that year. Given the uncertainty of the future growth of nuclear power and in the supply of oil and natural gas, coal-fired power plants could well provide up to 70 percent of the electric power in the United Stats by the end of the century.          

Yet, inspite of the fact that coal has long been a source of electricity and may remain one for many years (coal represents about 80 percent of the United States fossil-fuel reserves), it has actually never been the most desirable fossil fuel for power plants. Coal contain less energy per unit of weight than natural gas or oil; it is difficult to transport, and it is associated with a host of environmental issues, among them acid rain. Since the late 1960’s problems of emission control and waste disposal have sharply reduced the appeal of coal-fired power plants. The cost of ameliorating these environmental problems, along with the rising cost of building a facility as large and complex as a coal-fired power plant, has also made such plants less attractive from purely economic perspective.         

Change in the technological base of coal-fired power plants could restore their attractiveness, however. Whereas some of these changes are evoluntary and are intended mainly to increase the productivity of existing plants, completely new technologies for burning coal cleanly are also being developed.

The word “it” in paragraph 2 refers to ________         

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 following questions:

The rules of etiquette in American restaurants depend upon a number of factors the physical location of the restaurant, e.g., rural or urban; the type of restaurant, e.g., informal or formal; and certain standards that are more universal. In other words, some standards 5 of etiquette vary significantly while other standards apply almost anywhere. Learning the proper etiquette in a particular type of restaurant in a particular area may sometimes require instruction, but more commonly it simply requires sensitivity and experience. For example, while it is acceptable to read a magazine in a coffee shop, it is 10 inappropriate to do the same in a more luxurious setting. And, if you are eating in a very rustic setting it may be fine to tuck your napkin into your shirt, but if you are in a sophisticated urban restaurant this behavior would demonstrate a lack of manners. It is safe to say, however, that in virtually every restaurant it is unacceptable 15 to indiscriminately throw your food on the floor. The conclusion we can most likely draw from the above is that while the types and locations of restaurants determine etiquette appropriate to them, some rules apply to all restaurants. 

Question: What is the author’s main purpose in this passage?         

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 following questions:

The rules of etiquette in American restaurants depend upon a number of factors the physical location of the restaurant, e.g., rural or urban; the type of restaurant, e.g., informal or formal; and certain standards that are more universal. In other words, some standards 5 of etiquette vary significantly while other standards apply almost anywhere. Learning the proper etiquette in a particular type of restaurant in a particular area may sometimes require instruction, but more commonly it simply requires sensitivity and experience. For example, while it is acceptable to read a magazine in a coffee shop, it is 10 inappropriate to do the same in a more luxurious setting. And, if you are eating in a very rustic setting it may be fine to tuck your napkin into your shirt, but if you are in a sophisticated urban restaurant this behavior would demonstrate a lack of manners. It is safe to say, however, that in virtually every restaurant it is unacceptable 15 to indiscriminately throw your food on the floor. The conclusion we can most likely draw from the above is that while the types and locations of restaurants determine etiquette appropriate to them, some rules apply to all restaurants. 

Question: The author uses the phrase “safe to say” in order to demonstrate that the idea is___.        

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 following questions:

The rules of etiquette in American restaurants depend upon a number of factors the physical location of the restaurant, e.g., rural or urban; the type of restaurant, e.g., informal or formal; and certain standards that are more universal. In other words, some standards 5 of etiquette vary significantly while other standards apply almost anywhere. Learning the proper etiquette in a particular type of restaurant in a particular area may sometimes require instruction, but more commonly it simply requires sensitivity and experience. For example, while it is acceptable to read a magazine in a coffee shop, it is 10 inappropriate to do the same in a more luxurious setting. And, if you are eating in a very rustic setting it may be fine to tuck your napkin into your shirt, but if you are in a sophisticated urban restaurant this behavior would demonstrate a lack of manners. It is safe to say, however, that in virtually every restaurant it is unacceptable 15 to indiscriminately throw your food on the floor. The conclusion we can most likely draw from the above is that while the types and locations of restaurants determine etiquette appropriate to them, some rules apply to all restaurants. 

Question: According to the passage, which of the following is a universal rule of etiquette?         

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 following questions:

The rules of etiquette in American restaurants depend upon a number of factors the physical location of the restaurant, e.g., rural or urban; the type of restaurant, e.g., informal or formal; and certain standards that are more universal. In other words, some standards 5 of etiquette vary significantly while other standards apply almost anywhere. Learning the proper etiquette in a particular type of restaurant in a particular area may sometimes require instruction, but more commonly it simply requires sensitivity and experience. For example, while it is acceptable to read a magazine in a coffee shop, it is 10 inappropriate to do the same in a more luxurious setting. And, if you are eating in a very rustic setting it may be fine to tuck your napkin into your shirt, but if you are in a sophisticated urban restaurant this behavior would demonstrate a lack of manners. It is safe to say, however, that in virtually every restaurant it is unacceptable 15 to indiscriminately throw your food on the floor. The conclusion we can most likely draw from the above is that while the types and locations of restaurants determine etiquette appropriate to them, some rules apply to all restaurants. 

Question: What does the word “it” refer to line 5?         

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 following questions:

The rules of etiquette in American restaurants depend upon a number of factors the physical location of the restaurant, e.g., rural or urban; the type of restaurant, e.g., informal or formal; and certain standards that are more universal. In other words, some standards 5 of etiquette vary significantly while other standards apply almost anywhere. Learning the proper etiquette in a particular type of restaurant in a particular area may sometimes require instruction, but more commonly it simply requires sensitivity and experience. For example, while it is acceptable to read a magazine in a coffee shop, it is 10 inappropriate to do the same in a more luxurious setting. And, if you are eating in a very rustic setting it may be fine to tuck your napkin into your shirt, but if you are in a sophisticated urban restaurant this behavior would demonstrate a lack of manners. It is safe to say, however, that in virtually every restaurant it is unacceptable 15 to indiscriminately throw your food on the floor. The conclusion we can most likely draw from the above is that while the types and locations of restaurants determine etiquette appropriate to them, some rules apply to all restaurants. 

Question: Which of the following words is most similar to the meaning of “rustic”?           

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 following questions:

The rules of etiquette in American restaurants depend upon a number of factors the physical location of the restaurant, e.g., rural or urban; the type of restaurant, e.g., informal or formal; and certain standards that are more universal. In other words, some standards 5 of etiquette vary significantly while other standards apply almost anywhere. Learning the proper etiquette in a particular type of restaurant in a particular area may sometimes require instruction, but more commonly it simply requires sensitivity and experience. For example, while it is acceptable to read a magazine in a coffee shop, it is 10 inappropriate to do the same in a more luxurious setting. And, if you are eating in a very rustic setting it may be fine to tuck your napkin into your shirt, but if you are in a sophisticated urban restaurant this behavior would demonstrate a lack of manners. It is safe to say, however, that in virtually every restaurant it is unacceptable 15 to indiscriminately throw your food on the floor. The conclusion we can most likely draw from the above is that while the types and locations of restaurants determine etiquette appropriate to them, some rules apply to all restaurants. 

Question: With what topic is this passage primarily concerned?         

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 following questions:

The rules of etiquette in American restaurants depend upon a number of factors the physical location of the restaurant, e.g., rural or urban; the type of restaurant, e.g., informal or formal; and certain standards that are more universal. In other words, some standards 5 of etiquette vary significantly while other standards apply almost anywhere. Learning the proper etiquette in a particular type of restaurant in a particular area may sometimes require instruction, but more commonly it simply requires sensitivity and experience. For example, while it is acceptable to read a magazine in a coffee shop, it is 10 inappropriate to do the same in a more luxurious setting. And, if you are eating in a very rustic setting it may be fine to tuck your napkin into your shirt, but if you are in a sophisticated urban restaurant this behavior would demonstrate a lack of manners. It is safe to say, however, that in virtually every restaurant it is unacceptable 15 to indiscriminately throw your food on the floor. The conclusion we can most likely draw from the above is that while the types and locations of restaurants determine etiquette appropriate to them, some rules apply to all restaurants.  

Question: The word “manners” in line 8 could best be replaced by which of the following?