\(\left|31-17\right|-\left|13-57\right|=\left|14\right|-\left|-44\right|=14-44=-30\)

-30

\(A=\dfrac{13^{15}+1}{13^{16}+1}\)

\(\Leftrightarrow13A=\dfrac{13^{16}+13}{13^{16}+1}=1+\dfrac{12}{13^{16}+1}\)

\(B=\dfrac{13^{16}+1}{13^{17}+1}\)

\(\Leftrightarrow13B=\dfrac{13^{17}+13}{13^{17}+1}=1+\dfrac{12}{13^{17}+1}\)

mà \(13^{16}+1< 13^{17}+1\)

nên A>B

a)15.12-3.5.10

cách 1:

15.12-3.5.10= 15. 12- 15. 10

= 15.( 12-10)= 15.2= 30

cách 2:

15.12-3.5.10= 3.5 .12 -3.5.10= 3.(5.12- 5.10)= 3.( 60-50)

=3.10=30

a) Cách 1: 15.12 - 3.5.10 = 180 - 150

= 30

Cách 2 : 15.12 - 3.5.10 = 15.12 - ( 3.5 ) .10

= 15.12 - 15.10

= 15. ( 12 - 10 )

= 15.2

= 30

b) Cách 1 : 45 - 9.( 13 + 5 ) = 45 - 9.18

= 45 - 162

= -117

Cách 2 : 45 - 9.( 13+ 5 ) = 9.5 - 9.18

= 9.( 5 - 18 )

= 9. ( -13 )

= -117

c) Cách 1 : 29.( 19 - 13 ) - 19.( 29 - 13 ) = 29.6 - 19.16

= 174 - 304

= -130

Cách 2 : 29.( 19 - 13 ) - 19.( 29 - 13 )

= 29.19 - 29.13 - 19.29 + 19.13

= 19.13 - 29.13

= ( 19 - 29 ).13

= (-10) .13

= -130

16.19

=16.(20-1)

=320-16

=304

46.99

=46.(100-1)

=4600-46

=4554

35.98

=35.(100-2)

=3500-70

=3430

16.(20-1)=320-16=304

46.(100-1)=4600-46=4554

35.(100-2)=3500-70=3430

   Đây là câu trả lời của mình:

16.19 = 16( 20 - 1)= 320- 16 =304

46.99= 46.( 100-1)= 4600- 46= 4554

35.98= 35.( 100- 2) = 3500-70= 3430

a) 15 . 12 - 3 . 5 .10

= 15 . 12 - 15 . 10

= 15 ( 12 - 10)

= 15 . 2

= 30

b) 45 - 9 . ( 13 + 5 )

= 9 . 5 - 9. ( 13 + 5)

= 9 . [ 5 - ( 13 + 5)]

= 9 . [5 - 13 -5 ]

= 9 . (-13)

= -117

c) 29 . ( 19 - 13 ) - 19 . ( 29 - 13 )

= 29 . 19 - 29 . 13 - 19 . 29 + 19 . 13

= 29 . 13 - 19 . 13

= - 13. ( 29 -19 )

= - 13. 10

= - 130

~ Học tốt

# Chiyuki Fujito

a) 15.12-3.5.10

= 15.12-15.10

= 15.(12-10)

= 15.2

= 30

b) 45-9.(13+5)

= 45-9.18

= 45-162

= -117

c) 29.(19-13)-19.(29-13)

= 29.6-19.16

= 174-304

= -130

13. I enjoy listening to pop music best.

à  Pop music is my ……favorite kind of music………………………

14. They didn’t go camping yesterday because it rained heavily.

- It ……rained heavily so they didn't go camping yesterday…………………………

15. I started playing soccer 5 years ago.

à I have.......played soccer for 5 years.........................

16.Jack is 13 years old and my son is,too.

à Jack is ……the same age as my son…………

17. Mary was sick, so she could not go to school.

→ Because  ………Mary was sick, she could not go to school………………

18. The last time I met him was 3 years ago

→ I haven’t ………met him for 3 years……………………….

19. Lan went out because she finished her homework.(so)

→ Lan  …had finished her homework so she went out……………………………………

20. He is interested in doing morning exercise.

→ He enjoys ……doing morning exercise.………………………………………

21. We have learned English for 3 years.

→ We started ……learning E 3 years ago………………………………

22. We started to live here in 2012.

→ We have ........lived here since 2012..............................................

23. Her book is not the same as mine.

→ Her book is......different from mine....................................

24. You should walk around the Old Quarter at night.

→ It’s a good idea to.......... walk around the Old Quarter at night............................

1.  Pop music is my favorite kind of music.

2. It rained heavily yesterday so they didn't go camping.

3. I have played playing soccer for 5 years.

4. Jack is the same age as my son.

5. Because Mary was sick, she could not go to school.

6. I haven't met him for 3 years.

7. Lan finished her homework, so she went out.

8. He enjoys doing morning exercise.

9. We started to learn English for 3 years.

10. We have lived here since 2012.

11. Her book is different from mine.

12. It's a good idea to walk around the Old Quarter at night.

13. I enjoy listening to pop music best.

à  Pop music is my  favorite kind of music 

14. They didn’t go camping yesterday because it rained heavily.

- It it rained heavily , so they didn’t go camping yesterday

15. I started playing soccer 5 years ago.

à I have played soccer for 5 years

16.Jack is 13 years old and my son is,too.

à Jack is the same age as my son.

17. Mary was sick, so she could not go to school.

→ Because  Mary was sick , she could not go to school.

18. The last time I met him was 3 years ago

→ I haven’t seen him for 3 years

19. Lan went out because she finished her homework.(so)

→ Lan finished her homework ,so she went out.

20. He is interested in doing morning exercise.

→ He enjoys doing exercise in the morning

21. We have learned English for 3 years.

→ We started learning English 3 years ago 

22. We started to live here in 2012.

→ We have not lived here since 2012

23. Her book is not the same as mine.

→ Her book is diffirent from mine book 

24. You should walk around the Old Quarter at night.

→ It’s a good idea to walk around the Old Quarter at night.

 \(\Leftrightarrow\orbr{\begin{cases}2x-5=13\\2x-5=-13\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}2x=13+5\\2x=-13+5\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}2x=18\\2x=-8\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}x=18:2\\x=-8:2\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}x=9\\x=-4\end{cases}}\)

vậy \(x\in\left\{-4;9\right\}\)

| 2x - 5| = 13

TH1: 2x - 5 = 13

         2x      = 13 +5

         2x       = 18

         x          = 18:2

         x           = 9

TH2: 2x - 5 = -13

         2x      = ( -13) + 5

         2x      =  -8

           x      = (-8) : 2

           x      = -4

KL: x = 9, hoặc x =  -4

/2x-5/=13

suy ra : 2x-5 = 13 hoặc 2x-5 = -13

nếu 2x-5=13                      nếu 2x-5=-13

      2x   =13+5                        2x     = -13 +5

      2x   =18                           2x      =  8

       x    =18:2                         x       = 8:2

      x      = 9                           x       = 4

vậy x= 9 hoặc x =4

Bạn chưa có yêu cầu đề bài.

Bỏ hết trị tuyệt đối ra:

= 18 - 15 + 37

= 40

là 40 nhé

mình trả lời đầu tiên nên k mình 1 cái nha