\(\dfrac{x}{3}-\dfrac{1}{2}=\dfrac{1}{5}\\ \Leftrightarrow\dfrac{10x}{30}-\dfrac{15}{30}=\dfrac{6}{30}\\ \Leftrightarrow10x-15=6\\ \Leftrightarrow10x=21\\ \Leftrightarrow x=2,1\)

vậy phương trình có tập nghiệm là S={2,1}

31.

it said that he has been all over the world.

He is said to have been all over the world.

11 It was thought that you were selfish

12 The book was given to you by who?

13 she isn’t met

14. dragons have never been seen

15 I am hardly met at the beach.

16. -> the grammar is had to learn hard.

17. -> the floor is often swept by her every morning

18. –> the exercise isn’t could do.

19. -> he was known to steal the car

20 ->The question is too difficult to answer

a.

\(1000< 1024\\ \Rightarrow1000^{10}< 1024^{10}\\ \Rightarrow10^{30}< 2^{100}\)

suy ra A<B.

b.

\(27>25\\ \Rightarrow27^{150}>25^{150}\\ \Rightarrow3^{450}>5^{300}\)

suy ra A>B