Cho hàm số
liên tục, nhận giá trị dương trên đoạn
. Xét hình phẳng
giới hạn bởi đồ thị hàm số
, trục hoành và hai đường thẳng
,
. Khối tròn xoay được tạo thành khi quay hình phẳng
quanh trục
có thể tích là:
Hãy suy nghĩ và trả lời câu hỏi trước khi xem đáp án
$V = \pi \int_{a}^{b} [f(x)]^2 dx$.
Trong trường hợp này, $a = 1$ và $b = 4$, nên công thức trở thành:
$V = \pi \int_{1}^{4} [f(x)]^2 dx$.
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Chọn cặp từ/ cụm từ thích hợp nhất điền vào chỗ trống.
Nếu hội nhập kinh tế diễn ra theo xu hướng hòa đồng các giá trị thì hội nhập văn hóa - vấn đề cốt tử là phải bảo tồn cho được các giá trị _____, đó chính là _____ văn hóa của dân tộc.
Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the best answer to each of the following questions.
Taking Home the World Cup
Standing just 36 centimeters tall, the FIFA World Cup Trophy symbolizes the pinnacle of football achievement. Every four years, teams worldwide compete for it, but no one ever takes the trophy home. Made of 18-carat gold, the original trophy remains under FIFA's protection, with winners receiving only a replica. This measure safeguards it from theft, as the trophy has been stolen twice in its history.
The original trophy was made by a French sculptor, Abel LaFleur, and was called the “Jules Rimet Cup,” in honor of the founder of the World Cup tournament. Sometime during the first three World Cup events (1930, 1934, and 1938), the name changed to simply the “World Cup.” Then during World War II, not much was seen or heard of the trophy. It was being kept hidden in a shoe box under the bed of Dr. Ottorino Barassi, the Italian vice-president of FIFA, to prevent it from falling into the hands of the Nazi army. In 1966, the Cup was stolen during a public showing of the trophy prior to the World Cup tournament in England. Luckily, it was found a short time later, none the worse for wear, in a trash container by a little dog named Pickles. Four years later, Brazil earned permanent possession of the original trophy by winning its third World Cup title. Unfortunately, the trophy was stolen a second time in 1983 and was never recovered. The Brazilian Football Association had to have a duplicate trophy made.
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Happiness is a universal goal, yet its ingredients differ across societies and cultures. For some, safety and security are paramount, as demonstrated by Singapore. Known for its strict laws and highly regulated environment, Singapore provides a clean, orderly, and safe place for its citizens. The government ensures access to basic necessities such as housing and healthcare, significantly reducing poverty and promoting equality. While personal freedoms may be limited, many Singaporeans find satisfaction in the stability and quality of life their country offers, showing that happiness can stem from collective security.
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Phát biểu
Đúng
Sai
a
Sóng âm do còi báo động phát ra là sóng dọc.
b
Công suất của còi báo động càng giảm khi sóng càng truyền đi xa.
c
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d
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Nội dung nào sau đây không phải của Chính sách kinh tế mới ở Liên Xô?
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Cho mệnh đề: “Nếu tứ giác là một hình thoi thì trong tứ giác đó nội tiếp được một đường tròn”.
Mệnh đề đảo của mệnh đề trên là:
Read the following notice about a new travel platform and mark the letter A, B, C or D on your answer sheet to indicate the option that best fits each of the numbered blanks from 1 to 6
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Số proton và số neutron trong hạt nhân nguyên tử \(_{80}^{201}X\) là
Cặp chất nào sau đây là đồng phân của nhau?
Nhà sinh vật học nằm trong nhóm ngành nào?
Hiện tượng các NST co xoắn tối đa trước khi bước vào kì sau của quá trình nguyên phân có ý nghĩa gì?
Em hãy cho biết linh kiện tích cực là: