13.(29 - 113)+113.(13 - 29)

= 13.29 - 13.113+113.13 - 113.29

=(13.29 - 113.29)+(113.13 - 113.13)

=  29(13-113)    +   0

= 29.(-100)

=-2900

(617/191+29/33-115/117)*(1/4-1/5-1/20)

= (617/191+29/33-115/117)*(5/20-4/20-1/20)

=(617/191+29/33-115/117)*0

=0

\(\left(\dfrac{617}{191}+\dfrac{29}{33}-\dfrac{115}{117}\right)\times\left(\dfrac{1}{4}-\dfrac{1}{5}-\dfrac{1}{20}\right)\\ =\left(\dfrac{617}{191}+\dfrac{29}{33}-\dfrac{115}{117}\right)\times0\\ =0\)

a)  5 8 . − 2 9 + 5 8 . − 7 9 + 1 1 3 . − 5 8 = 5 8 − 2 9 + − 7 9 + − 4 3 = − 35 24

b)  8 5 7 + 3 , 15 + 1 2 7 + 4 , 35 = 8 5 7 + 1 2 7 + ( 3 , 15 + 4 , 35 ) = 14 , 5

a)  5 8 . − 2 9 + 5 8 . − 7 9 + 1 1 3 . − 5 8 = 5 8 − 2 9 + − 7 9 + − 4 3 = − 35 24

b)  8 5 7 + 3 , 15 + 1 2 7 + 4 , 35 = 8 5 7 + 1 2 7 + 3 , 15 + 4 , 35 = 14 , 5

113 x 49 + 113 x 44 - 113

= 113 x 49 + 113 x 44 - 113 x 1

= 113 x (49 + 44 - 1) 

= 113 x 92

= 10396

113 x 49 + 113  x 44 - 113

= 113 x ( 49 + 44 - 1 )

= 113 x  92

= 10396

113 x 49 + 113 x 44 - 113 

= 113 x 49 + 113 x 44 - 113 x 1

= 113 x ( 49 + 44 - 1 )

= 113 x ( 93 - 1 )

= 113 x 92

= 10396

c. TH1:/-8/=8

=8+(-2).3

=8-6=2

TH2:/-8/=8

=-8+(-2).3

=-8.(-6)

=-48

d.-887.(113+457)+113(887-457)

=-887.570+113.430

=-505590+48590

=-457000

e.(16+39)+(158-16-39)

=55+103

=158

c, \(\left|-8\right|+\left(-2\right).3\) => \(8+\left(-6\right)\) = \(2\)

d, \(-887.\left(113+457\right)+113.\left(887-457\right)\)

=> \(\left(-887\right).113+\left(-887\right).457+113.887-113.\left(457\right)\)

=> \(\left[\left(-887\right).113+113.887\right]+\left[\left(-887\right).457-113.457\right]\)

=> \(\left[113.\left(887-887\right)\right]+\left[457.\cdot\left(-113-887\right)\right]\)

=> \(\left[113.0\right]+\left(457.-1000\right)\)

=> \(0+-457000=-457000\)

e, \(\left(16+39\right)+\left(158-16-39\right)\)

=> \(\left(16+39+158-16-39\right)\)

=> \(\left(16-16\right)+\left(39-39\right)+158\)

=> \(0+0+158=158\)

Ta thấy: 29 = 15 * 2 -1   ; 57 =29*2-1 ; 113 =57*2 -1

 Vậy 3 số tiếp theo là 113*2-1 =225  ; 225*2 -1 =449 ;  449*2-1=897

*Nhận xét:  Bất kì một số trong dãy số (trừ số đầu tiên) thì bằng 2 lần số đứng trước nó trừ đi 1

a. 54 x 113 + 45 x 113 + 113

= 113 x (54 + 45 + 1)

= 113 x 100 = 11300

Vậy giá trị cần tìmlaf: 11300

b. 54 x 47 - 47 x 53 - 20 - 27

= 54 x 47 - 47 x 53 - (20 + 27)

= 54 x 47 - 47 x 53 - 47

= 47 x (54 - 53 - 1)

= 47 x 0 = 0

Vậy giá trị cần tìm là: 0

\(a,54\times113+45\times113+113\\ =113\times\left(54+45+1\right)\\ =113\times100=11300\)

\(b,54\times47-47\times53-20-27\\ =54\times47-47\times53-47\\ =47\times\left(54-53-1\right)\\ =47\times0=0\)

a 11300

 b  0