BỎ DẤU NGOẶC RỒI TÍNH :

1. - 7264 + ( 1543 + 7264 )

= ( - 7264 ) + 1543 + 7264 

= [ ( - 7264 ) + 7264 ] + 1543

= 0 + 1543

= 1543

2. (144 - 97 ) - 144

= 144 + ( - 97  ) + (- 144 )

= [ 144 +( - 144) ]  + ( -97 )

= 0 + (- 97)

= - 97

3. ( - 145 ) - ( 18 - 145 )

= ( -145 ) + ( - 18 ) + 145 

= [ ( -145 ) + 145 ] + ( -18 )

=  0 + ( - 18)

= - 18

4. 111 + ( - 11 + 27 )

= 111 + ( - 11 ) + 27

= ( 111 + 27 ) + ( -11 )

= 138 + ( -11 )

= 127

5. ( 27 + 541 ) - ( 486 - 73 )

= 27 + 541 + ( - 486) + 73 

= ( 27 + 73 ) + [ 541 + ( - 486 )]

= 100 + 55

= 155

6. ( 36 + 79 ) + ( 145 - 79 - 36)

= 36 + 79 + 145 + ( - 79 ) + ( - 36 )

= [ 36 + ( - 36)] + [ 79 + ( -79 )] + 145

= 0 + 0 + 145 

= 145

7. 10 - [ 12 - ( -9 - 1) ]

= 10 + ( - 12 ) + 9 + ( -1 )

= ( 10 + 9 ) + [ ( -12 ) + ( - 1) ]

= 19 + ( - 13 )

= 6

8. ( 38 - 29 + 43 ) - (43 + 38 )

= 38 + ( - 29 ) 43 + ( -43 ) +( -  38)

= [ 38 + ( - 38 )] + [ 43 + ( - 43 ) ] + ( - 29 )

= 0 + 0 + ( - 29 )

= - 29

9. 274 - [ ( - 43 ) + 271 - ( - 17 )]

= 274 + 43 + ( - 271 ) + 17

= [ 274 + ( - 271 ) ] + ( 43 + 17 )

= 3 + 60

=  63

10. - 144 - [ 29 - ( + 144 ) - ( + 144 )

= ( - 144 ) + ( - 29 ) +  144 +( - 144 ) 

= [ ( - 144 ) + 144 ] + [ ( -29) + ( - 144 ) ]

= 0 + ( - 173 )

= - 173 

k cho mk nếu đúng . Sai thì thôi nhé . ahihi

= 

\(1.-7264+\left(1543+7264\right)\)

\(=-7264+1543+7264\)

\(=1543\)

\(2.\left(144-97\right)-144\)

\(=144-97-144\)

\(=-97\)

\(3.\left(-145\right)-\left(18-145\right)\)

\(=-145-18+145\)

\(=-18\)

\(4.111+\left(-11\right)+27\)

\(=111-11+27\)

\(=100+27\)

\(=127\)

\(5.\left(27+541\right)-\left(486-73\right)\)

\(=27+541-486+73\)

\(=\left(27+73\right)+\left(541-486\right)\)

\(=100+55\)

\(=155\)

các câu còn lại tương tự phá ngoặc ra nha

Câu này thì mik ko chắc chắn cho lắm nha bạn : BỎ NGOẶC RỒI TÍNH

271 - [ (-43) + 271 - (-17)]

= 271 - ( - 43 + 271 + 17 ) 

= 271 + 43 - 271 - 17

= ( 271 - 271) + ( 43 - 17 )

= 26

Ta có: \(A=\frac{1}{2^2}+\frac{1}{4^2}+\frac{1}{6^2}+\frac{1}{8^2}+\frac{1}{10^2}+\frac{1}{12^2}+\frac{1}{14^2}\)

              \(=\frac{1}{2^2}\left(1+\frac{1}{2^2}+\frac{1}{3^2}+\frac{1}{4^2}+\frac{1}{5^2}+\frac{1}{6^2}+\frac{1}{7^2}\right)\)  

            \(< \frac{1}{2^2}\left(1+\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+\frac{1}{4.5}+\frac{1}{5.6}+\frac{1}{6.7}\right)\)  

            \(=\frac{1}{2^2}\left(1+1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{5}+\frac{1}{5}-\frac{1}{6}+\frac{1}{6}-\frac{1}{7}\right)\)

             \(=\frac{1}{2^2}\left(2-\frac{1}{7}\right)=\frac{1}{2}-\frac{1}{28}< \frac{1}{2}\)

 Vậy   \(A< \frac{1}{2}\).

1/ - 7264 + ( 1543 + 7264 )

= - 7264 + 1543 + 7264

= ( - 7264 + 7264 ) + 1543  

= 0 + 1543

= 1543

2/ ( 144 - 97 ) - 144

= 144 - 97 - 144  

= ( 144 - 144 ) - 97 

= 0 - 97

= - 97

3/ ( - 145 ) - ( 18 - 145 )

= - 145 - 18 - 145

= ( - 145 - 145 ) - 18 

= ( - 290 ) - 18

= - 308

Thế thôi nhé

1/ - 7264 + ( 1543 + 7264 )

= - 7264 + 1543 + 7264

= ( - 7264 + 7264 ) + 1543

= 0 + 1543

= 1543

K mk nha

1 bài nha

Làm hết chắc mk chết 

Làm rõ nhiều bài

Suy nghĩ đi chứ

Chưa chi đã hỏi

Ta thấy \(\frac{3}{4}=\frac{1}{1^2}-\frac{1}{2^2};\frac{5}{36}=\frac{1}{2^2}-\frac{1}{3^2};...\)

Tổng quát:  \(\frac{2n+1}{n^2\left(n+1\right)^2}=\frac{\left(n+1\right)^2-n^2}{n^2\left(n+1\right)^2}=\frac{1}{n^2}-\frac{1}{\left(n+1\right)^2}\)

Đặt \(A=\frac{3}{4}+\frac{5}{36}+...+\frac{2n+1}{n^2\left(n+1\right)^2}\)

\(\Rightarrow A=1-\frac{1}{2^2}+\frac{1}{2^2}-\frac{1}{3^2}+...+\frac{1}{n^2}-\frac{1}{\left(n+1\right)^2}\)

\(A=1-\frac{1}{\left(n+1\right)^2}\)

Do \(\left(n+1\right)^2>0\Rightarrow A< 1.\)

-7264 + ( 1543 + 7264 )

=-7264 + 1543 + 7264

=1543

 (144 - 97 ) -144

=144 - 97 - 144

=-97

 ( -145 ) - ( 18 -145 ) 

= -145 - 18 - 145

=-308

 111 + ( -11 + 27 ) 

=111 - 11 + 27

=127

 ( 27+ 514 ) - (486-73)

=27 + 514 - 486 - 73

=-18

 ( 36 + 79 ) + ( 145 - 79 - 36 ) 

=36 + 79 + 145 - 79 - 36

=145

 ( 38 -29+ 43 ) - ( 43 + 38 ) 

=38 - 29 + 43 - 43 + 38

=47

 271 - [ ( -43 ) + 271 - ( -17)] 

= 271 + 43 + 271 + 17

=602

 -144  - [ 29 - ( + 144 ) - ( + 144 ) ] 

=-144 - 29 - 144 - 144

=-461

hok tốt !

a) -7264+(1543 +7264)           b) (144-97)-144                                c)(-145)-(18-145)

=(-7264)+1543+7264                  =144-97-144                                    =(-145)-18+145

=  [(-7264)+7264]+1543             =(144-144)-97                                  =[(-145)+145}-18

=0+1543                                     =0-97                                             = 0-18

=1543                                         = -97                                                = -18

-7264 + ( 1543 + 7264 )

=-7264 + 1543 + 7264

=1543

 (144 - 97 ) -144

=144 - 97 - 144

=-97

 ( -145 ) - ( 18 -145 ) 

= -145 - 18 - 145

=-308

 111 + ( -11 + 27 ) 

=111 - 11 + 27

=127

 ( 27+ 514 ) - (486-73)

=27 + 514 - 486 - 73

=-18

 ( 36 + 79 ) + ( 145 - 79 - 36 ) 

=36 + 79 + 145 - 79 - 36

=145

 ( 38 -29+ 43 ) - ( 43 + 38 ) 

=38 - 29 + 43 - 43 + 38

=47

 271 - [ ( -43 ) + 271 - ( -17)] 

= 271 + 43 + 271 + 17

=602

 -144  - [ 29 - ( + 144 ) - ( + 144 ) ] 

=-144 - 29 - 144 - 144

=-461

\(G=\frac{3}{4}+\frac{5}{36}+\frac{7}{144}+....+\frac{2n+1}{n^2.\left(n+1\right)^2}=\frac{3}{1.4}+\frac{5}{4.9}+...+\frac{2n+1}{n^2\left(n^2+2n+1\right)}=1-\frac{1}{4}+\frac{1}{4}-\frac{1}{9}+...+\frac{1}{n^2}-\frac{1}{n^2+2n+1}\)

\(=1-\frac{1}{n^2+n+1}\left(n>0\right)\Rightarrow1-\frac{1}{n^2+n+1}

tui ko rảnh mà gõ cái trên nhưng có chơi free fire

bạn rank j rồi

tui chs, rank vàng( mùa trc k cương)

Bài 1

1/ (-37) +14 +26 + 37

= [(-37) + 37] + 14 + 26

= 40

2/ (-24) + 6 + 10 + 24

= [(-24) + 24] + 6 + 10

= 16

3/ 15 + 23 + (-25) + (-23)

= 15 + (-25) + [23 + (-23)]

= -10

4/ 60 + 33 + (-50) + (-33)

= [33 + (-33)] + 60 + (-50)

= 10

5/ (-16) + (-209) + (-14) + 209

= [(-209) + 209] + (-16) + (-14)

= -30

6/ (-12) + (-13) + 36 + (-11)

= (-25) + 25 = 0

7/ (-16) + 24 + 16 - 34

= [(-16) + 16] + (24 - 34)

= -10

8/ 25 + 37 - 48 - 25 - 37

= (25 - 25) + (37 - 37) - 48

= -48

9/ 2575 + 37 - 2576 - 29

= (2575 - 2576) + (37 - 29)

= -1 + 8 = 7

10/ 34 + 35 + 36 + 37 -14 -15- 16 - 17

= (37 - 17) + (36 - 16) + (35 - 15) + (34 - 14)

= 10 + 10 + 10 + 10 = 40

Bài 2

1/ -7264 + (1543 + 7264)

= -7264 + 1543 + 7264

= 1543

2/ (144 - 97) - 144

= 144 - 97 - 144

= - 97

3/ (-145) - (18 - 145)

= (-145) - 18 + 145

= - 18

4/ 111 + (-11 + 27)

= 111 - 11 + 27

= 127

5/ ( 27 + 514) - (486 - 73) 

= 27 + 514 - 486 + 73

= (27 + 73) + ( 514 - 486)

= 100 + 28 = 128

6/ (36 + 79) + (145 - 79 - 36)

= 36 + 79 + 145 - 79 - 36

= (36 - 36) + ( 79 - 79) + 145 = 145

7/ 10 - [12 - (- 9 - 1)]

= 10 - [12 - (- 10)]

= 10 - [12 + 10] = 10 - 12 - 10 = - 12

8/ (38 - 29 + 43) - (43 + 38)

= 38 - 29 + 43 - 43 - 38

= (38 - 38) + (43 - 43) - 29 = - 29

9/  271 - [(-43) + 271 - (-17)]

= 271 - [(-43) + 271 + 17]

= 271 + 43 - 271 - 17

= (271 - 271) + 43 - 17 = 26

10/ -144 - [29 - (+ 144) - (+144)]

= - 144 - [29 - 144 - 144]

= -144 - 29 + 144 + 144

= (- 144 + 144) - 29 + 144

= 115

XONG RỒI NHÌN SỐ MUỐN ĐAU MẮT !!!!!!!!!!!!!!!!!!!!!!

Bài 1 : bỏ dấu ngoặc rồi tính.

1, -7264+(1543+7264)

\(=-7264+1543+7264\)

\(=-8807+7264\)

\(=-1543\)

2, ( 144-97) - 144

\(=144-97-144\)

\(=47-144\)

\(=-97\)

3, ( -145) - ( 18- 145)

\(=-145-18+145\)

\(=-163+145\)

\(=18\)

4, 111+ ( -11+27)

\(=111+\left(-11\right)+27\)

\(=100+27\)

\(=127\)

5, ( 27+ 514) -( 486-73)

\(=27+514-486+73\)

\(=541-486+73\)

\(=55+73\)

\(=128\)

6, ( 36 + 79) + ( 145-79-36)

\(=36+79+145-79-36\)

\(=115+145-79-36\)

\(=260-79-36\)

\(=145\)

7, 10-[12-(- 9-1)]

\(=10-12+9+1\)

\(=8\)

8, ( 38-29+43) -( 43+38)

\(=38-29+43-43-38\)

\(=-29\)

9, 271-[(-43)+271-(-17)]

\(=271+43-271+17\)

\(=60\)

10, -144-[29-(+144)-(+144)]

\(=-144-29-144-144\)

\(=-461\)