Ex1

1 give

2 wake 

3 hurry

4 pick

5 stand

6 get

7 tidy

Ex2

1 put

2 turn

3 try

4 carry

5 get

Ex3

1 up

2 off

3 on

4 over

5 round

6 down

\(\dfrac{19}{20}-x=\dfrac{8}{5}+\dfrac{3}{4}\)
\(\dfrac{19}{20}-x=\dfrac{32}{20}+\dfrac{15}{20}\)
\(\dfrac{19}{20}-x=\dfrac{47}{20}\)
\(x=\dfrac{19}{20}-\dfrac{47}{20}\)
\(x=\dfrac{-28}{20}=\dfrac{-7}{5}\)

\(\dfrac{19}{20}-x=\dfrac{8}{5}+\dfrac{3}{4}\\ \dfrac{19}{20}-x=\dfrac{47}{20}\\ x=\dfrac{19}{20}-\dfrac{47}{20}\\ x=-\dfrac{28}{20}\\ x=-\dfrac{7}{5}.\)

tối thiểu 1-7 câu

5.

\(sin\left(60^o+2x\right)=-1\)

\(\Leftrightarrow60^o+2x=-90^o+k.360^o\)

\(\Leftrightarrow x=-75^o+k.180^o\)

6.

\(sin\left(2x+1\right)=\dfrac{1}{3}\)

\(\Leftrightarrow\left[{}\begin{matrix}2x+1=arcsin\dfrac{1}{3}+k2\pi\\2x+1=\pi-arcsin\dfrac{1}{3}+k2\pi\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{1}{2}arcsin\dfrac{1}{3}-\dfrac{1}{2}+k\pi\\x=\dfrac{\pi}{2}-\dfrac{1}{2}arcsin\dfrac{1}{3}-\dfrac{1}{2}+k\pi\end{matrix}\right.\)

Cách làm : 

sina = \(\dfrac{1}{2}\) ⇔ \(\left[{}\begin{matrix}a=\dfrac{\pi}{6}+k2\pi\\a=\dfrac{5\pi}{6}+k2\pi\end{matrix}\right.\)

sina = \(-\dfrac{\sqrt{3}}{2}\) ⇔ \(\left[{}\begin{matrix}a=-\dfrac{\pi}{3}+k2\pi\\a=\dfrac{4\pi}{3}+k2\pi\end{matrix}\right.\)

sina = 1 ⇔ \(a=\dfrac{\pi}{2}+k.2\pi\)

sina = 0 ⇔ \(a=k\pi\)

sina = -1 ⇔ \(a=-\dfrac{\pi}{2}+k.2\pi\)

sina = \(\dfrac{1}{3}\) ⇔ \(\left[{}\begin{matrix}a=arcsin\left(\dfrac{1}{3}\right)+k2\pi\\a=\pi-arcsin\left(\dfrac{1}{3}\right)+k2\pi\end{matrix}\right.\)

Với a là một đa thức xác định trên R

3.

\(sin\left(\dfrac{x}{2}-45^o\right)=1\)

\(\Leftrightarrow\dfrac{x}{2}-45^o=90^o+k.360^o\)

\(\Leftrightarrow x=270^o+k.720^o\)

4.

\(sin\left(3x+\dfrac{\pi}{3}\right)=0\)

\(\Leftrightarrow3x+\dfrac{\pi}{3}=k\pi\)

\(\Leftrightarrow3x=-\dfrac{\pi}{3}+k\pi\)

\(\Leftrightarrow x=-\dfrac{\pi}{9}+\dfrac{k\pi}{3}\)

1.A

2.D

3.B

5.A

7.C

8.B

9.B

11.B

12.D

13.A

14.D

15.C

16.B

17.A

18.B

This letter will be translated into Vietnamese.

Mình làm phần I trước nhé.....cái ảnh dưới đó

1 B

2 A

4 C

5 A

6 B

7 B

8 D

9 B

10 B

11 A

12 B

13 A

14 B

15 B

16 C

17 C

Phần 2

1 A

2 D

3 B

4 C

5 A

7 C

8 B

9 B

11 B

12 D

13 C

14 D

15 C

16 B

17 A

18 D