Ta có:
x = x1 + x2 + x3
= 4√2 cos(2t+π/4) + 4cos(2t-π/2) + 5cos(2t+π)
= 1cos(2t+π)
Phương trình dao động tổng hợp của vật là: x=1cos(2t+π) cm
Vậy biên độ dao động tổng hợp của vật là: 1cm
Núi uốn mình,trong chiếc áo the xanh Đồi thoa son nắm dưới ánh bình minh Hãy tìm ra biện pháp tu từ và phân tích tác dụng của mỗi câu trên,giúp mik với ạ
IV.Use the correct form of the word given in each sentence: (1.5pts) 1 . The local people showed me great……………………(hospitable) . 2 . It’s……………..…...(help) to have a calculator for this exam . 3 . He has been…………………..(award) a scholarship to do research . 4 . He always gives his opinions…………………...(clear) . 5 . I am not really…………………..…(suit) dressed for a party . 6 . The bride wore a dress that she…………………….(design) herself
Tính giá trị của các biểu thức sau: a) C = xyz – (xy + yz + zx) + x + y + z – 1 , với x = 9; y = 10; z = 11. b) D = x³ - x ²y - xy ² + y ³ , với x = 5,75 ; y = 4,25
Cm: m chia 3 dư 2 thì m+1 chia hết cho 3
III. Put the correct form of the words in brackets. 1. The weather in Da Lat is often__________________. (change) 2. My best friend is caring and ________________. (rely) 3. What subjects do you _______________ in? (special) 4. Thank you for your __________________. (invite) 5. The _______________ here is so beautiful. (scene) PART C. DIALOG COMPLETION Circle the sentence that best completes each of the following exchanges. 1. Cara: “Excuse me, where are the changing rooms?” Shop assistant: “_______________” A. Sorry, I don’t get in. B. They’re over there, Miss. C. Can you exchange your clothes? Giáo Viên Chuyên Anh - Thầ y Bùi Văn Vinh - 0988.333.599 8 D. Here you are. 2. Seller: “________________” Tom: “ I’d like a kilo of beef, please.” A. Hello. How can I help you? B. What did you eat? C. What should I do? D. Here’s your chance. 3. Nina: “_____________ romantic comedies?” Rachel: “ In my opinion, they’re both funny and touching.” A. Are you interested in B. What about C. What do you think about D. Do you enjoy 4. Bill: “You have such an incredible house!” Bob: “__________________” A. Thanks. B. I hope that you will drop in. C. It costs an arm and a leg. D. Nothing much. 5. Kelly: “It’s time for us to recycle things to protect the environment.” Jane: “___________” A. It’s too late. B. We have a lot of time. Don’t worry! C. I completely agree with you. D. Do you think it’s possible? giúp mik với
Bài 1: Cho parabol (P) : y = `x^2` và đường thẳng (d) : y= 3mx + 1 - `m^2` ( m là tham số) a) TÌm m để (d) đường thẳng đi qua A( 1; -9)
Tìm tập hợp các điểm M, biết : xM = 0; y M thuộc R ( vẽ đồ thị )
tam giác abc có góc a bằng 30 độ góc b bằng 45 độ bc bằng 8cm. Tính AB
Mọi người làm giúp em bài này với ạ em cần nộp lúc 9h
mình vote 5 sao cho tất cả nhá Câu 45 The team played _____ and lost the match. A worst B badly C worth D bad Câu 46 A city is _____ than the country. A more exciting B the most exciting C excited D exciting Câu 47 This is the best music I have ever heard. A This is the first time I‘ve heard this good music. B I‘ve ever heard so good music as this. C I‘ve ever heard such a good music as this. D I’ve never heard better music than this. Câu 48 Peter’s very _____ at tennis. He won the game. A best B well C better D good Câu 49 Please listen _____ . A carely B care C carefully D careful Câu 50 Everybody was very _____ about you. A worry B worried C worrying D worringly
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