\(a.20-\left[30-\left(5-1\right)^2\right]\)                             \(b.75-\left(3.5^2-4.2^3\right)\)

\(=20-\left[30-4^2\right]\)                                       \(=75-\left(75-4.2^3\right)\)

\(=20-14=6\)                                          \(=75-\left(75-32\right)\)

                                                                 \(=75-43=32\)

Bài 2: Tính nhanh

 

a) 29 + 132 + 237 + 868 + 3

 = 29+(132+858)+(237+3)

=29+990+240

=1259

 

29+132+237+868+3

29+(132+868)+(237+3)

29+1000+240

29+(1000+240)

29+1240

1269

bài 2 :

a) 29 + 132 + 237 + 868 + 3

= 29 +(132 + 868)+(237 + 3)

= 29 + 1000 + 240

=1269

b) 35 . 34 + 35 . 86 + 65 . 75 + 65 . 5
= 35 .(34 + 86)+ 65 .(75 + 5)

= 35 . 120 + 65 . 80

= 4200 + 5200

= 9400

c) 3 . 25 . 8 + 4 . 37 . 6 + 2 . 38 .12

khum bít làm hehe

d) 12 . 53 + 53 . 172 - 53 . 84

= 53 . (12 + 172 - 84)

= 53 . 100

= 5300

Bài 3:

a) 4 . 52 - 18 : 32 hình như câu này sai đề

b) 32 . 22 - 32 . 19

= 32 . (22 - 19)

= 32 . 3

= 96

 c) 24 . 5 - [131- (13 - 4)^2]   = 24 . 5 - [131 - 9^2]   = 24. 5 - [131 - 81]   = 24 . 5 - 50   = 120 - 50   = 70   d) 5871: [928 – ( 247 - 82) . 5] + 21750   = 5871 : [928 - 165 . 5] + 21750 = 5871 : [928 - 825] + 21750 = 5871 : 103 + 21750 = 57 + 21750  = 21807

`600:{30:[401-(4.153-4.53)]}`
`600:{30:[401-(4.(153-3))]}`
`=600:[30:(401-4.100)]`
`=600:(30:1)`
`=600:30=20`

\(600:\left\{30:\left[401-\left(4.153-4.53\right)\right]\right\}\) 

\(=600:\left\{30:\left[401-\left(4.\left(153-53\right)\right)\right]\right\}\) 

\(=600:\left\{30:\left[401-\left(4.100\right)\right]\right\}\) 

\(=600:\left\{30:\left[401-400\right]\right\}\) 

\(=600:\left\{30:1\right\}\) 

\(=600:30\) 

\(=20\)

A, =47.(-1).12+12.(-53)

    =(-47).12+12.(-53)

     =[(-47)+(-53)].12

    =-100.12

    =-1200

   

Thực hiện phép tính (tính nhanh nếu có thể)

a, 47.(-12) + 12. (-53)

=(-47).12+12.(-53)

=12.[-47+(-53)]

=12.(-100)

=-1200

b, 106. (-3 - 105) - 106.(-105)

=106.[-3-105-(-105)]

=106.(-3)

=-318

\(a,47.\left(-12\right)+12.\left(-53\right)\)

\(=47.\left(-1\right).12+12.\left(-53\right)\)

\(=-47.12+12.\left(-53\right)\)

\(=12.\left[-47+\left(-53\right)\right]\)

\(=12.\left(-100\right)=-1200\)

\(b,106.\left(-3-105\right)-106.\left(-105\right)\)

\(=106.\left[-3-105-\left(-105\right)\right]\)

\(=106.\left(-3\right)=-318\)

a) \(3.5^2+15.2^2-26\div2\)

= 3.25 + 15.4 - 13

= 75 + 60 - 13

= 135 - 13

= 122

b) \(5^3.2-100\div4+2^3.5\)

= 125.2 - 25 + 8.5

= 250 - 25 + 40

= 225 + 40

= 265

c)\(6^2\div9+50.2-3^3.33\)

= 36 : 9 + 100 - 9.33

= 4 + 100 - 297

= 104 - 297

= -193

d)\(3^2.5+2^3.10-81\div3\)

= 9.5 + 8.10 - 27

= 45 + 80 - 27

= 125 - 27

= 98

e) \(5^{13}\div5^{10}-25.2^2\)

= 5³ - 25.4

= 125 - 100

= 25

f) \(20\div2^2+5^9\div5^8\)

= 20 : 4 + 5

= 5 + 5

= 10

a) \(17+188+183=205+183=388\)

b) \(80-\left[130-\left(12-4\right)^2\right]\)

\(=80-\left(130-64\right)\)

\(80-66=14\)

c) \(2^3.17-2^3.14\)

\(8.17-8.14\)

\(=8.\left(17-14\right)\)

\(=8.3=24\)

a) 2.5³-3.2+4⁵:4³
= 2.125-6+16
= 250+10
= 260

250-6 + 4^5-3 =>250-6 + 4² =>250-6 + 16 =>260

=260