Mấy bn giúp mik vs, mik cảm ơn
K
Khách
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Những câu hỏi liên quan
LH
1
T
1 tháng 10 2023
a) Diện tích xung quanh của khối rubik là:
\(\dfrac{1}{2}\cdot234\cdot67,5=7897,5\left(mm^2\right)\)
Diện tích mỗi mặt của khối rubik là:
\(7897,5:3=2632,5\left(mm^2\right)\)
Diện tích toàn phần của khối rubik là:
\(2632,5\cdot4=10530\left(mm^2\right)\)
\(---\)
b) Thể tích của khối rubik là:
\(\dfrac{1}{3}\cdot2632,5\cdot63,7=55896,75\left(mm^3\right)\)
Vậy: ...
#\(Toru\)
10 tháng 11 2021
a) \(\Leftrightarrow\left(3x+1\right)\left(x-1\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{1}{3}\\x=1\end{matrix}\right.\)
b) \(\Leftrightarrow\left(2x-5\right)\left(2x+5\right)-\left(2x-5\right)\left(2x+7\right)=0\\ \Leftrightarrow\left(2x-5\right)\left(2x+5-2x-7\right)=0\\ \Leftrightarrow-2\left(2x-5\right)=0\\ \Leftrightarrow2x-5=0\\ \Leftrightarrow x=\dfrac{5}{2}\)
c) \(\Leftrightarrow2\left(x+3\right)-x\left(x+3\right)=0\\ \Leftrightarrow\left(x+3\right)\left(2-x\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=-3\\x=2\end{matrix}\right.\)
d) \(\Leftrightarrow\left(x+3\right)\left(x^2-3x+9\right)+\left(x+3\right)\left(x-9\right)=0\\ \Leftrightarrow\left(x+3\right)\left(x^2-3x+9+x-9\right)=0\\ \Leftrightarrow\left(x+3\right)\left(x^2-2x\right)=0\\ \Leftrightarrow x\left(x+3\right)\left(x-2\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=0\\x=-3\\x=2\end{matrix}\right.\)
1/ 1c 2d 3b 4a 5d 6c 7b 8d 9b 10c
2/
1. unless I arrive early
2. I were you, I would
3. is fine, we will
4. will prepare everything
5. weren't broken, I could
6. if I haven't got
7. the lights would be
3/
1. My father told me not to stay up so late again
2. Beth asked if it was going to rain the next day
3. Sonia asked her husband to help her with the washing-up
4. Lisa said that her cousin was coming the next month
5. Alice told Sally that she would give her a ring that night she if she finished work early
6. Peter said that he had never ridden on a roller coaster before and it had been amazing
7. Angle asked Tom what time his flight to Sydney left
8. Andrew told Martha to stop making so much noise as he was trying to get some sleep
1. C
2. D
3.B
4. A
5. D
6. C
7. B
8. D
9. B
10. C
.
1. The secretary has told me that unless I arrive early, I will miss my interview.
2. If I were you, I would see a doctor.
3. If the weather is good enough, we will go on a day trip.
4. If my camera didn't break, I would lend it to you.
6. I won't go to John's barbecue if I haven't got time.
7. If Martha were at home, she would turn the light on.
.
1. My father advised me not to stay up late.
2. Beth asked if it was going to rain the next day.
3. Sonia asked her husband to help her with the washing-up.
4. Lisa said her cousin was coming the next month.
5. Alice said to Salley that if she finished work early, she would give her a ring that night.
6. Peter said he had never ridden on a roller coaster before and it had been amazing.
7. Angie asked Tom what time his flight to Sydney left.
8. Andrew told Martha to stop making so much noise because she was trying to get some sleep.
.
1. works - will pass
2. had - would buy
3. come - will
4. will feel - don't give
5. closed
6. goes - will be
7. knows - don't reveal
8. have
9. won
10. will stop