Giúp mik với mik dò
K
Khách
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Những câu hỏi liên quan
DT
Đỗ Thanh Hải
CTVVIP
11 tháng 9 2021
Tham khảo
1. Someone will clean the room today. =>THE ROOM WILL BE CLEANED TODAY
2. Someone might steal the car. =>THE CAR MIGHT BE STOLEN
3. They had to cut down that tree.=>THAT TREE HAD TO BE CUT DOWN
4. They're going to demolish the old houses.=>THE OLD HOUSES ARE GOING TO BE DEMOLISHED
5. We can't restore the picture. =>THE PICTURE CAN'T BE RESTORED
6. You must make an appointment in advance.=>AN APPOINTMENT MUST BE MADE IN ADVANCE
7. I don't want people to make me a fool. =>I DON'T WANT TO BE MADE A FOOL
8. Someone has to look after the garden.=>THE GARDEN HAS TO BE LOOKED AFTER
9. He wants everybody to serve him. =>HE WANTS TO BE SERVED
10. They're going to interview him next week=>HE IS GOING TO BE INTERVIEWED NEXT WEEK
DT
Đỗ Thanh Hải
CTVVIP
11 tháng 9 2021
Tham khảo
1. Someone will clean the room today. =>THE ROOM WILL BE CLEANED TODAY
2. Someone might steal the car. =>THE CAR MIGHT BE STOLEN
3. They had to cut down that tree.=>THAT TREE HAD TO BE CUT DOWN
4. They're going to demolish the old houses.=>THE OLD HOUSES ARE GOING TO BE DEMOLISHED
5. We can't restore the picture. =>THE PICTURE CAN'T BE RESTORED
6. You must make an appointment in advance.=>AN APPOINTMENT MUST BE MADE IN ADVANCE
7. I don't want people to make me a fool. =>I DON'T WANT TO BE MADE A FOOL
8. Someone has to look after the garden.=>THE GARDEN HAS TO BE LOOKED AFTER
9. He wants everybody to serve him. =>HE WANTS TO BE SERVED
10. They're going to interview him next week=>HE IS GOING TO BE INTERVIEWED NEXT WEEK
PN
1
MN
3 tháng 7 2021
\(n_{NaOH}=0.015\cdot2=0.03\left(mol\right)\)
\(n_{H_2SO_4}=0.015\cdot1.5=0.0225\left(mol\right)\)
\(2NaOH+H_2SO_4\rightarrow Na_2SO_4+H_2O\)
\(0.03..........0.015...........0.015\)
\(n_{H_2SO_4\left(dư\right)}=0.0225-0.015=0.0075\left(mol\right)\)
\(C_{M_{Na^+}}=\dfrac{0.015\cdot2}{0.015+0.015}=1\left(M\right)\)
\(C_{M_{H^+}}=\dfrac{0.0075\cdot2}{0.015+0.015}=0.5\left(M\right)\)
\(C_{M_{SO_4^{2-}}}=\dfrac{0.015+0.0075}{0.015+0.015}=0.75\left(M\right)\)
PN
2
HP
29 tháng 7 2021
\(\left|cosx\right|=\dfrac{1}{2}\)
\(\Leftrightarrow\left[{}\begin{matrix}cosx=\dfrac{1}{2}\\cosx=-\dfrac{1}{2}\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=\pm\dfrac{\pi}{3}+k2\pi\\x=\pm\dfrac{\pi}{2}+k2\pi\end{matrix}\right.\)
\(\Leftrightarrow x=\pm\dfrac{\pi}{3}+k2\pi\)
NV
Nguyễn Việt Lâm
Giáo viên
29 tháng 7 2021
\(\left|cosx\right|=\dfrac{1}{2}\)
\(\Leftrightarrow cos^2x=\dfrac{1}{4}\)
\(\Leftrightarrow\dfrac{1+cos2x}{2}=\dfrac{1}{4}\)
\(\Leftrightarrow cos2x=-\dfrac{1}{2}\)
\(\Rightarrow2x=\pm\dfrac{2\pi}{3}+k2\pi\)
\(\Rightarrow x=\pm\dfrac{\pi}{3}+k\pi\)
NN
18 tháng 10 2016
Thì là vs nơi ơ, ăn uống hợp vệ sinh, rửa tay trc khi ăn và sau khi đại tiện... nhìu lắm bn ak ;)
5 tháng 3 2022
Câu 3:
a: \(BD=\sqrt{BC^2-DC^2}=4\left(cm\right)\)
b: \(\widehat{A}=180^0-2\cdot70^0=40^0< \widehat{B}\)
nên BC<AC=AB
c: Xét ΔEBC vuông tại E và ΔDCB vuông tại D có
BC chung
\(\widehat{EBC}=\widehat{DCB}\)
Do đó:ΔEBC=ΔDCB
d: Xét ΔOBC có \(\widehat{OBC}=\widehat{OCB}\)
nên ΔOBC cân tại O
KV
31 tháng 10 2023
Câu 2
a) Thay y = -2 vào biểu thức đã cho ta được:
2.(-2) + 3 = -1
Vậy giá trị của biểu thức đã cho tại y = -2 là -1
b) Thay x = -5 vào biểu thức đã cho ta được:
2.[(-5)² - 5] = 2.(25 - 5) = 2.20 = 40
Vậy giá trị của biểu thức đã cho tại x = -5 là 40
