Đề sai rồi bạn

Đề hình như bị sai đk bạn

1 lived 

2 wasn't hearing - was thinking

3 walked - was

4 were you doing - phoned

5 was reading - heard

6 was walking - saw

7 had watched - wrote

8 met

9 had you done - moved

10 was - didn't attend

II

1 when we were having lunch

2 had read the instruction, I started the machine

3 went out for a rest, we had finished our assignment

4 she left, it was raining

5 learning English

6 to help me

7 the man to open the briefcase

8 my friend break the bottle

9 him fall off the bike

10 a foreign language in a short time is not easy

\(2\cdot3^x-1=53\\ \Leftrightarrow2\cdot3^x=54\\ \Leftrightarrow3^x=27\\ \Leftrightarrow x=3\)

\(2\cdot3^x-1=53\\ 2\cdot3^x=54\\ 3^x=27\\ 3^x=3^3=>x=3\)

\(...\Rightarrow2.3^x=54\)

\(\Rightarrow3^x=27\)

\(\Rightarrow3^x=3^3\)

\(\Rightarrow x=3\)

Câu 7: D

Câu 8: B

Câu 9: B

1,D

2,B

3,B

7: D

 8: B

 9: B

pặn bị bắt kóc hẻ :) ?

🙂??

ảnh lỗi rồi !

\(A=\left\{x\in Z|\left(x^2-9\right)\left(x^2-7\right)\left(3x+5\right)=0\right\}\)

Giải pt \(\left(x^2-9\right)\left(x^2-7\right)\left(3x+5\right)=0\) \(\left(dk:x\in Z\right)\)

\(\Leftrightarrow\left[{}\begin{matrix}x^2-9=0\\x^2-7=0\\3x+5=0\end{matrix}\right.\) \(\Leftrightarrow\left[{}\begin{matrix}x=\pm3\left(tm\right)\\x=\pm\sqrt{7}\left(ktm\right)\\x=-\dfrac{5}{3}\left(ktm\right)\end{matrix}\right.\)

Vậy \(A=\left\{-3;3\right\}\)

cần chi tiết ko bạn

hay mỗi đáp án nhợ

Ta có:\(\sqrt{14-2\sqrt{33}}\)=1,584573983

\(\sqrt{33-4\sqrt{33}}\)=3,165714677

=>1,584573983\(-\)3,165714677=-1,581140694

nhé bạn

what ?