1 rained here since January

it rained was in January

2 played tennis for 2 hours

my sister started playing tennis

3 seen such an interesting film

seen sucn an interesting film

4 lived here since monday

5 ate this kind of food 2 years ago

eaten this kind of food for 2 years

6 we have been here

7 is it since you saw Lan

\(P=tanx\left(\dfrac{1+cos^2x}{sinx}-sinx\right)\)

\(=tanx.\dfrac{1+cos^2x-sin^2x}{sinx}\)

\(=\dfrac{sinx}{cosx}.\dfrac{2cos^2x}{sinx}=2cosx\)

quan hệ giữa hai người bạn là quan hệ thắm thiết ,gắn bó,hòa hợp như một thể thống nhất.Hai ng bạn cùng chung tâm trạng hiền,vui gặp gỡ

Bài 22: 

a: \(=\cos54^0\)

d: \(=\tan63^0\)

2a

4c

6d

7c

8c

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1 drove->drive

4 will ride->is riding

Bài 3:

Ta có: \(A=\dfrac{\sqrt{x}-5}{\sqrt{x}+2}=\dfrac{\sqrt{x}+2-7}{\sqrt{x}+2}=1-\dfrac{7}{\sqrt{x}+2}\)

A nguyên khi \(\dfrac{7}{\sqrt{x}+2}\) nguyên:

\(\Rightarrow7\) ⋮ \(\sqrt{x}+2\)  

\(\Rightarrow\sqrt{x}+2\inƯ\left(7\right)=\left\{1;-1;7;-7\right\}\)

Mà: \(\sqrt{x}+2\ge2\)

\(\Rightarrow\sqrt{x}+2\in\left\{7\right\}\)

\(\Rightarrow x\in\left\{25\right\}\)

Câu 14: C