Giúp mình với, mai nộp rồi
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E
1 aren't going to play
2 isn't going to walk
3 am not going to have
4 is going
5 am going to watch
6 aren't going
7 am not going to finish
8 are not going to buy
Bài 3 :
(A) : Fe3O4
(B) : FeO
(D) : Fe
(E) : FeS
(F) : SO2
(G) : SO3
(H) : H2SO4
\(3Fe_2O_3 + CO \xrightarrow{t^o} 2Fe_3O_4 + CO_2\\ Fe_3O_4 + CO \xrightarrow{t^o} 3FeO + CO_2\\ FeO + CO \xrightarrow{t^o} Fe +C O_2\\ Fe + S \xrightarrow{t^o} FeS\\ 4FeS +75O_2 \xrightarrow{t^o} 2Fe_2O_3 +4SO_2\\ 2SO_2 + O_2 \xrightarrow{t^o} 2SO_3\\ SO_3 + H_2O \to H_2SO_4\\ 2FeS + 10H_2SO_4 \to Fe_2(SO_4)_3 + 9SO_2 + 10H_2O\)
\(\left\{{}\begin{matrix}2x+y=1\\x+y=-1\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=2\\x+y=-1\end{matrix}\right.\Leftrightarrow}\left\{{}\begin{matrix}x=2\\y=-3\end{matrix}\right.\)
\(\left\{{}\begin{matrix}2x+2y=18\\x-y=-6\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x+y=9\\x-y=-6\end{matrix}\right.\Leftrightarrow}\left\{{}\begin{matrix}2x=3\\x-y=-6\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=\dfrac{3}{2}\\y=\dfrac{15}{2}\end{matrix}\right.\)\(\left\{{}\begin{matrix}2x+3y=6\\x-2y=3\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}4x+6y=12\\3x-6y=9\end{matrix}\right.\Leftrightarrow}\left\{{}\begin{matrix}7x=21\\3x-6y=9\end{matrix}\right.\Leftrightarrow}\left\{{}\begin{matrix}x=3\\y=0\end{matrix}\right.\)
1 makes
2 doesn't eat
3 goes
4 Do-go
5 Do-agree
6 does-come
7 does-work
8 doesn't -water
9 do-do
10 Do they eat
11 am
12 rises
13 is
14 doesn't read
15 watches
Ex2
1. you don't go to school everyweekday
Do you go to school every weekday?
2. Lan doesn't play badminton with her friends today
Does Lan play badminton with her friends today?
3. Hoa doesn't like reading story books
Does Hoa like reading story books
4. Lien and Lan don't in the same class
Do Lien and Lan in the same class
5. Ba's father doesn't work in a big factory with my father
Does Ba's father work in a big factory with my father
6 She doesn't study English very well
Does she study English very well
7 They don't tall and thin
Do they tall and thin
8 His mother doesn't cook dinner for the family everyday
Does his mother cook dinner for the family everyday
9 Hoa's mother doesn't go shopping this morning
Ex3
1. Lan usually reads book recess
2 Does Ba go to the market every Sunday
3 Her father often rides his motorbike
4 Nam doesn't have short black hair
5 She usually gets up early
4:
a: A=1/3(1+1/2+...+1/64)
Đặt B=1+1/2+...+1/64
=>2B=2+1+...+1/32
=>B=2-1/64=127/64
=>A=1/3*127/64=127/192
b: =5/2(1-1/3+1/3-1/5+...+1/11-1/13)
=5/2*12/13
=60/26=30/13
Bài 3:
a: Ta có: \(x^2+5x+5xy+25y\)
\(=x\left(x+5\right)+5y\left(x+5\right)\)
\(=\left(x+5\right)\left(x+5y\right)\)
b: Ta có: \(x^2-y^2+14x+49\)
\(=\left(x+7\right)^2-y^2\)
\(=\left(x+7-y\right)\left(x+7+y\right)\)
26. D
27. C
28. C
29. D
30. A
31. C
32. A
33. B
34. B
38. C
39. C
40. B
1. hang out
2. will you do
3. to go
4. to send
5. making
V.
1. Pollution
2. destroyed
3. electricity
4. inventor
5. dangerous
6. natural
7. famous
8. interesting
VI.
1. is
2. was driving
3. have not met
4. was doing
5. get
6. has not watched
7. will pick
8. likes
9. go/ go
10. will be watching
11. are not
12. did not go/ stayed
13. had finished
14. visit
15. is cooking / is reading
16. has seen
17. had hired