Giúp mình nha, mình cám ơn ạ !
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1 Sue wishes she hadn't bought that new book
2 Unless you walk faster, you will be late
3 Carol spent 2 hours fixing the television sets
4 I make these handicrafts by myself
5 If I were you, I would take the bus instead of the train
II
1 She doesn't have to get up early on Saturday
2 Children mustn't be left alone in car
3 John must explain this if he want his student to succeed
4 I have to file the report this week
5 We don't have to work overtime on Saturdays
6 You mustn't drive more than 25 mph in this zone
7 She didn't have to attend the presentation yesterday
8 She has to pick up her children at school
9 You don't have to arrive before 8
10 They had to visit the doctor yesterday as they didn't feel well
a) điện trở tương đương của đoạn mạch
Rtđ = R1 + R2 =10 + 20= 30 (Ω)
Cường độ dòng điện chạy qua đoạn mạch
I = \(\dfrac{U}{Rtđ}=\dfrac{6}{30}=0,2\left(A\right)\)
pollution
amazing
why didn't hoa go to school yesterday - Because she had a bad cold
What kind of movies do you enjoy - mostly comedies
How many people atted .... - more than 6 million
are people's lives.... - Yes of course
Do you think ... - I think population...
22.pollution
23.amazed
24.
1 vàng với 2 xanh
2 vàng với 1 xanh
3 vàng với 5 xanh
4 vàng với 4 xanh
5 vàng với 3 xanh
tui kh bic cậu còn cần kh nhma đây nhéeeee
22/ \(\omega A=8\pi\)
\(A^2=x^2+\dfrac{v^2}{\omega^2}\Leftrightarrow A^2=3,2^2+\dfrac{\left(4,8\pi\right)^2}{\omega^2}\)
\(\Leftrightarrow\omega^2A^2=3,2^2\omega^2+23,04\pi^2\Leftrightarrow64\pi^2=3,2^2.\omega^2+23,04\pi^2\Leftrightarrow\omega=2\pi\left(rad/s\right)\)
\(\Rightarrow f=\dfrac{\omega}{2\pi}=\dfrac{2\pi}{2\pi}=1\left(Hz\right)\Rightarrow D.1Hz\)
23/ \(\omega A=20;\omega^2A=80\Rightarrow\left\{{}\begin{matrix}\omega=4\left(rad/s\right)\\A=5cm\end{matrix}\right.\)
\(\Rightarrow v=\omega\sqrt{A^2-x^2}=4.\sqrt{5^2-4^2}=12\left(cm/s\right)\Rightarrow A.12cm/s\)
a: ĐKXĐ: \(x\notin\left\{10;-10;\sqrt{10};-\sqrt{10}\right\}\)
b: \(A=\dfrac{5x^3+50x+2x^2+20+5x^3-50x-2x^2+20}{\left(x^2-10\right)\left(x^2+10\right)}\cdot\dfrac{x^2-100}{x^2+4}\)
\(=\dfrac{10x^3+40}{\left(x^2-10\right)\left(x^2+10\right)}\cdot\dfrac{x^2-100}{x^2+4}\)
1 C
2 D
3 A
4 B
5 D