`@` `\text {Ans}`

`\downarrow`

`2023 \times 14 + 2023 \times 83+97`

`= 2023 \times (14+83) + 97`

`= 2023 \times 97 + 97`

`= 196231 +97`

`= 196328`

`78 \times 31+78 \times 24+78 \times 17+78 \times 22 \times 72`

`= 78 \times (31+24+17+22 \times 72)`

`= 78 \times (31+24+17+1584)`

`= 78 \times 1656`

`= 129168`

`371 \times 69+371 \times 14+629 \times 83`

`= 371 \times (69+14) + 629 \times 83`

`= 371 \times 83 + 629 \times 83`

`= 83 \times (371+629)`

`= 83 \times 1000`

`= 83000`

`91 \times 51+49 \times 163-49 \times 72`

`= 91 \times 51 + 49 \times (163-72)`

`= 91 \times 51+49 \times 91`

`= 91 \times (51+49)`

`= 91 \times 100`

`= 9100`

`3 \times 12 \times 17 + 4 \times 9 \times 81 + 2 \times 6 \times 6`

`= 9 \times 4 \times 17 + 4 \times 9 \times 81 + 4 \times 9 \times 2`

`= 9 \times 4 \times (17+81+2)`

`= 36 \times 100` 

`= 3600`

`42 \times 17 + 58 \times 83 \times 42 \times 83 + 42 \times 83 + 17`

`= 17 \times (42+58) + 42 \times 83 \times (58 \times 83 +1)`

`= 17 \times 100 + 3486 \times 4815`

`= 1700 + 16785090`

`= 16786790`

a) (-124) + 24 = -100
b) 37. 78 + 37. 22
=  37 . ( 78 + 22 )
=  37 . 100
= 3700

\(a) (-124) + 24 = -100 b) 37. 78 + 37. 22 = 37 . ( 78 + 22 ) = 37 . 100 = 3700\)

a) (- 124) + 24                                          b) 37 . 78 + 37 . 22

= - ( 124 - 24)                                              =37 . ( 78 + 22)

= - 100                                                        =37 . 100 

                                                                    3700

a/ 35*18-35*28=35*(-10)=-350

b.45-5.(12+9)=45-45-60=-60

c.24.(16-5) -16.(24-5)= 24.16 - 24.5 - 16.24 - 16.5= 0 -120 - 80= -200

1, 35 . 18 - 5 . 7 . 28

= 35 . 18 - 35 . 28

= 35 . ( 18 - 28 )

= 35 . ( -10 )

= -350

2, 45 - 5 . ( 12 + 9 )

= 40 . 21

= 840

3, 24 . ( 16 - 5 ) - 16 . ( 24 - 5 )

= 24 . 11 - 16 . 19

= 264 - 304

= -40

78.31+78.68+78

=78.31+78.68+78.1

=78.(31+68+1)

=78.100

=7800

1024:(2².7+2².25)

=1024:[2².(7+25)]

=1024:128

=8

24-[20-(5-1)²]

=24-[20-4²]

=24-[20-16]

=24-4

=20

x³=64

=>x³=4³

=>x=4

2^x+1=128

2^x.2¹=128

2^x=128:2

2^x=64

2^x=2⁶

=>x=6

a ) 7800

b) 8

c)20

tim x

a)x=4

b) x = 6

a) 78 x 31 + 78 x 68 + 78

= 78 x ( 31 + 68 + 1 )

= 78 x 110

= 78 x 11 x 10

= 858 x10

= 8580

b) 1024 : ( 2² x 7 + 2²  x 25 )

= 1024 :  [ 2² x ( 7 + 25 ) ]

= 1024 : [ 2² x 32 ]

= 1024 : [ 2² x 2⁵ ]

= 2¹⁰ : 2⁷

= 2³

Đáp án cần chọn là: C

1) 12 x 19 + (3 x 4) x 24 - (6 x 2) x 33

   = 12 x19 + 12 x 24 -12 x 33

   = 12 x (19 + 24 - 33)

   = 12 x 10

   =120

2) 35 x1001-35

   =35 x (1001 - 1)

   = 35 x 1000 

   = 35 000

1) 12 x 19 + (3 x 4) x 24 - (6 x 2) x 33

   = 12 x19 + 12 x 24 -12 x 33

   = 12 x (19 + 24 - 33)

   = 12 x 10

   =120

2) 35 x1001-35

   =35 x (1001 - 1)

   = 35 x 1000 

   = 35 000

1) 12 x 19 + (3 x 4) x 24 - (6 x 2) x 33

   = 12 x19 + 12 x 24 -12 x 33

   = 12 x (19 + 24 - 33)

   = 12 x 10

   =120

2) 35 x1001-35

   =35 x (1001 - 1)

   = 35 x 1000 

   = 35 000

-1 ≤ x ≤ 5 mà x ∈ Z. Do đó: x ∈ { -1 ; 0 ; 1 ; 2 ; 3 ; 4 ; 5 }

\(1\frac{13}{15}.0,75-\left(\frac{104}{195}+25\%\right).\frac{24}{47}-3\frac{12}{13}:3\)

\(=\frac{28}{15}.\frac{3}{4}-\left(\frac{8}{15}+\frac{1}{4}\right).\frac{8}{9}-\frac{51}{13}.\frac{1}{3}\)

\(=\frac{7}{5}-\left(\frac{32}{60}+\frac{15}{60}\right).\frac{8}{9}-\frac{17}{13}\)

\(=\frac{7}{5}-\frac{47}{60}.\frac{8}{9}-\frac{17}{13}\)

\(=\frac{7}{5}-\frac{94}{135}-\frac{17}{13}\)

\(=\frac{-212}{351}\)

Tự quy đồng

\(2\frac{3}{4}.\left(-0,4\right)-1\frac{3}{5}.2,75+\left(-1,2\right):\frac{4}{11}\)

\(=\frac{11}{4}.\frac{-2}{5}-\frac{8}{5}.\frac{11}{4}-\frac{6}{5}.\frac{11}{4}\)

\(=\frac{11}{4}.\left(\frac{-2}{5}-\frac{8}{5}-\frac{6}{5}\right)\)

\(=\frac{11}{4}.\frac{-16}{5}\)

\(=\frac{-44}{5}=-8\frac{4}{5}\)