1 send - will receive 

2 do - will improve

3 find - will give

4 will go - has

5 will go- gets

6 doesn't phone - will leave

7 don't study - won't pass

8 rains - won't have to

9 won't be able - watch

10 can't move - isn't

11 study - will pass

.-.-.-.-.-.-.-.-.-.-.

Kiểm tra? :/

hình như dg thi mà

Đường tròn (C) tâm \(I\left(1;-1\right)\) bán kính \(R=4\)

Gọi \(I'\left(x';y'\right)\) là tâm \(\left(C'\right)\) \(\Rightarrow I'\) là ảnh của I qua phép vị tự nói trên đồng thời \(R'=\left|k\right|R\)

\(\left\{{}\begin{matrix}x'=1+k\left(1-1\right)=1\\y'=-1+k\left(-1+1\right)=-1\end{matrix}\right.\)

Phương trình (C'):

\(\left(x-1\right)^2+\left(y+1\right)^2=16k^2\)

Thế tọa độ M vào ta được:

\(\left(4-1\right)^2+\left(3+1\right)^2=16k^2\Rightarrow k^2=\dfrac{25}{16}\)

\(\Rightarrow k=\pm\dfrac{5}{4}\)

Câu 16

B

Câu17

C

P6:

1. big

2. been

3. bought

4. people

P7:

1. T

2. F

3. F

4. F

=2+2+...+2+613

=613+32

=645

23. Please take the form from your teacher and ask her to sign.

24. Can you show me the nearest way to the post office

25. We are going to plant the flowers in the parks and water them in the afternoon.

26. My brother is very good at repairing household appliances.

\(I=\int\dfrac{2}{2+5sinxcosx}dx=\int\dfrac{2sec^2x}{2sec^2x+5tanx}dx\\ =\int\dfrac{2sec^2x}{2tan^2x+5tanx+2}dx\)

We substitute :

\(u=tanx,du=sec^2xdx\\ I=\int\dfrac{2}{2u^2+5u+2}du\\ =\int\dfrac{2}{2\left(u+\dfrac{5}{4}\right)^2-\dfrac{9}{8}}du\\ =\int\dfrac{1}{\left(u+\dfrac{5}{4}\right)^2-\dfrac{9}{16}}du\\ \)

Then, 

\(t=u+\dfrac{5}{4}\\I=\int\dfrac{1}{t^2-\dfrac{9}{16}}dt\\ =\int\dfrac{\dfrac{2}{3}}{t-\dfrac{3}{4}}-\dfrac{\dfrac{2}{3}}{t+\dfrac{3}{4}}dt\)

Finally,

\(I=\dfrac{2}{3}ln\left(\left|\dfrac{t-\dfrac{3}{4}}{t+\dfrac{3}{4}}\right|\right)+C=\dfrac{2}{3}ln\left(\left|\dfrac{tanx+\dfrac{1}{2}}{tanx+2}\right|\right)+C\)