GT: \(\text{(O;R)}\cap\text{(O';r)}\) lần lượt tại A;B| O;O'\(\in\) 2 nửa mặt phẳng bờ AB. Vẽ cát tuyến PAQ\(\left(P\in\left(O\right);Q\in\left(O'\right)\right)\)
KL: Khi nào A nằm giữa P;Q
Hộ mik vs nha. Thanks nhiều!
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
NT
1
29 tháng 4 2019
4P + 5O2 => 2P2O5
P2O5 + 3H2O => 2H3PO4
2H3PO4 + 3Zn => Zn3(PO4)2 + 3H2
H2 + 1/2 O2 => H2O
2H2O => 2H2 + O2
2O2 + 3Fe => Fe3O4
Fe3O4 + 4CO => 3Fe + 4CO2
Fe + 2HCl => FeCl2 + H2
H2 + CuO => Cu + H2O
Cu + 1/2 O2 => CuO
DT
0
NT
0
16 tháng 12 2017
1.What is she doing in the kitchen?
2.What would you ?
3.What's Miss Nga do?
4.Is Nam often flies a kite?
5.What lessons do you have on Monday and Saturday?
6.How often is he go to the cinema?
7.What grade is your sister in?
8.What time does Mai have dinner?
9.What is your brother would?
10.What does Linh have for her breakfast
29 tháng 5 2018
Dat cau hoi cho phan bi gach chan o moi cau sau
1 She is cooking meal in thẻ kichen
->..................What is she doing in the kichen?.....................................................
2: I'd some milk and vergetables .
->.....................What would you ?..................................
2 tháng 9 2018
bài 1: ta có : \(cos^220+cos^240+cos^250+cos^270\)
\(=cos^220+cos^270+cos^240+cos^250\)
\(=cos^220+cos^2\left(90-20\right)+cos^240+cos^2\left(90-40\right)\)
\(=cos^220+sin^220+cos^240+sin^240=1+1=2\)
bài 2: a) ta có : \(cot^2\alpha-cos^2\alpha=cos^2\alpha\left(\dfrac{1}{sin^2\alpha}-1\right)=cos^2\alpha.\left(\dfrac{1-sin^2\alpha}{sin^2\alpha}\right)\)
\(=cos^2\alpha.\left(\dfrac{cos^2\alpha}{sin^2\alpha}\right)=cos^2\alpha.cot^2\alpha\left(đpcm\right)\)
b) ta có : \(sin^2\alpha+cos^2\alpha=1\Leftrightarrow sin^2\alpha=1-cos^2\alpha\)
\(\Leftrightarrow sin^2\alpha=\left(1-cos\alpha\right)\left(1+cos\alpha\right)\Leftrightarrow\dfrac{1+cos\alpha}{sin\alpha}=\dfrac{sin\alpha}{1-cos\alpha}\left(đpcm\right)\)
1 tháng 1 2022
IV. Viết lại các câu sau sao cho nghĩa không đổi:
1. Her old house is bigger than her new one.
=> Her new house..is smaller than her old one.
2. No one in my class is taller than Peter.
=> Peter..is the tallest student in my class.
3. The black dress is more expensive than the white one.
=> The white dress.....cheaper than the black one.
4. According to me, English is easier than Maths.
=> According to me, Maths....is more difficult than English.
5. No one in my group is more intelligent than Mary.
=> Mary....is the most intelligent person in my group.
6. No river in the world is longer than the Nile.
=> The Nile.....is the longest river in the world.
1 tháng 1 2022
7. Mount Everest is the highest mountain in the world.
=> No mountain....in the world is higher than Mount Everest.
8. This is the first time I have ever met such a pretty girl.
=> She is..the prettiest girl I have ever met.
9. He works much. He feels tired.
=> The more...she works, the more she feels tired.
10. This computer works better than that one.
=> That computer...works worse than this one.
11. The apartment is big. The rent is high.
=> The bigger......the apartment is, the high the rent is.
12. We set off soon. We will arrive soon.
=> The sooner.......we set off, the sooner we will arrive.
13 tháng 10 2017
Theo đề bài ta có: \(\widehat{M_1}+2\widehat{N_1}=245^o\left(1\right)\)
Mà \(\widehat{M_1}+\widehat{N_1}=180^o\) (2 góc trong cùng phía của a//b) (2)
Lấy (1) trừ (2) ta có:
\(\left(\widehat{M_1}+2\widehat{N_1}\right)-\left(\widehat{M_1}+\widehat{N_1}\right)=245^o-180^o\)
\(\Rightarrow\widehat{M_1}+2\widehat{N_1}-\widehat{M_1}-\widehat{N_1}=65^o\)
\(\Rightarrow\widehat{N_1}=65^o\)
Thay \(\widehat{N_1}=65^o\) vào (2) ta có:
\(\widehat{M_1}+65^o=180^o\)
\(\Rightarrow\widehat{M_1}=180^o-65^o=115^o\)
Ta có:
\(\widehat{N_2}=\widehat{M_1}=115^o\) (2 góc so le trong của a//b)
\(\widehat{M_2}=\widehat{N_1}=65^o\) (2 góc so le trong của a//b)
Vậy \(\widehat{N_2}=115^o;\widehat{M_2}=65^o\)
NM
5