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A Thuw
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Toru
7 tháng 10 2023 lúc 17:48

Bài 1.

\(a,\left(2^4\cdot3\cdot5^2\right):\left\{450:\left[450-\left(4\cdot5^3-2^3\cdot5^2\right)\right]\right\}\)

\(=\left(16\cdot3\cdot25\right):\left\{450:\left[450- \left(4\cdot125-8\cdot25\right)\right]\right\}\)

\(=\left(48\cdot25\right):\left\{450:\left[450-\left(500-200\right)\right]\right\}\)

\(=1200:\left[450:\left(450-300\right)\right]\)

\(=1200:\left(450:150\right)\)

\(=1200:3\)

\(=400\)

\(---\)

\(b,3^3\cdot5^2-20\left\{90-\left[164-2\cdot\left(7^8:7^6+7^0\right)\right]\right\}\)

\(=27\cdot25-20\left\{90-\left[164-2\cdot\left(7^2+1\right)\right]\right\}\)

\(=675-20\left\{90-\left[164-2\cdot\left(49+1\right)\right]\right\}\)

\(=675-20\left[90-\left(164-2\cdot50\right)\right]\)

\(=675-20\left[90-\left(164-100\right)\right]\)

\(=675-20\left(90-64\right)\)

\(=675-20\cdot26\)

\(=675-520\)

\(=155\)

\(---\)

\(c,\left[\left(18^7:18^6-17\right)\cdot2022-1986\right]\cdot5\cdot1^{2022}-13^2\cdot2020^0\)

\(=\left[\left(18-17\right)\cdot2022-1986\right]\cdot5\cdot1-169\cdot1\)

\(=\left(1\cdot2022-1986\right)\cdot5-169\)

\(=\left(2022-1986\right)\cdot5-169\)

\(=36\cdot5-169\)

\(=180-169\)

\(=11\)

Bài 2.

\(a) (2^x+1)^2+3\cdot(2^2+1)=2^2\cdot10\\\Rightarrow (2^x+1)^2+3\cdot(4+1)=4\cdot10\\\Rightarrow (2^x+1)^2+3\cdot5=40\\\Rightarrow (2^x+1)^2+15=40\\\Rightarrow (2^x+1)^2=40-15\\\Rightarrow (2^x+1)^2=25\\\Rightarrow (2^x+1)^2= (\pm 5)^2\\\Rightarrow \left[\begin{array}{} 2^x+1=5\\ 2^x+1=-5 \end{array} \right.\\ \Rightarrow \left[\begin{array}{} 2^x=4\\ 2^x=-6 (vô.lí) \end{array} \right. \\ \Rightarrow 2^x=2^2\\\Rightarrow x=2\)

Vậy \(x=2\).

\(---\)

\(b)3\cdot(x-7)+2\cdot(x+5)=41\\\Rightarrow 3\cdot x+3\cdot(-7)+2\cdot x+2\cdot5=41\\\Rightarrow 3x-21+2x+10=41\\\Rightarrow (3x+2x)+(-21+10)=41\\\Rightarrow 5x-11=41\\\Rightarrow 5x=41+11\\\Rightarrow 5x=52\\\Rightarrow x=\dfrac{52}{5}\)

Vậy \(x=\dfrac{52}{5}\).

\(Toru\)

Apple NGUYỄN
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Nguyễn Thị Thu Hiền
24 tháng 9 2015 lúc 12:27

 

100:{250:[450-(4.53-22.25)}]

=100:{250:[450-(500-100)]}

=100:{250:[450-400]}

=100:{250:50}

=100:5

=20

 

Trần Ngọc Bảo Chi
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Nguyễn Trường Huy
31 tháng 7 2019 lúc 14:49

  100:{250:[450-(4.5^3-2^2.25)]}

=100:{250:[450-(4.125-4.25)]}

=100:{250:[450-(500-100)]}

=100:{250:[450-400]}

=100:{250:50}

=100:5

=20

                             ~Chúc học tốt!~

Nguyễn Bách Tâm Đan
31 tháng 7 2019 lúc 14:52

\(100:\left\{250:\left[450-\left(4.5^3-2^2.25\right)\right]\right\}\)

\(100:\left\{250:\left[450-\left(2^2.5^3-2^2.5^2\right)\right]\right\}\)

\(100:\left\{250:\left[450-2^2.5^2\left(5-1\right)\right]\right\}\)

\(100:\left[250:\left(450-100.4\right)\right]\)

=\(100:\left(250:50\right)\)

\(100:5\)

\(20\)

NGUYỄN THỊ THÙY LINH
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Nguyễn Lê Phước Thịnh
5 tháng 11 2021 lúc 21:51

a: \(=32-76=-44\)

b: \(=20-30+4^2=-10+16=6\)

Pham Trong Bach
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Cao Minh Tâm
18 tháng 7 2019 lúc 8:52

a,  600 : { 450 : 450 - 4 . 5 3 - 2 3 . 5 2 }

= 600:{450:[450 - (4.125 - 8.25)]} = 600:{450:[450 - (500 - 200)]}

= 600:{450:[450 - 300]} = 600:{450:150} = 600:3 = 200

b,  18 . { 420 : 6 - 150 - ( 68 . 2 - 2 3 . 5 ) }

= 18.{70 - [150 - (68.2 - 8.5)]} = 18.{70 - [150 - (136 - 40)]}

= 18.{70 - [150 - 96]} = 18.{70 - 54} = 18.16 = 288

Thảo Nguyễn
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Dương Hồng Bảo Phúc
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HT.Phong (9A5)
14 tháng 9 2023 lúc 7:15

a) \(26+173+74+27\)

\(=\left(26+74\right)+\left(173+27\right)\)

\(=100+200\)

\(=300\)

b) \(75\cdot37+89\cdot46+75\cdot52-89\cdot21\)

\(=75\cdot\left(37+52\right)+89\cdot\left(46-21\right)\)

\(=75\cdot89+89\cdot25\)

\(=89\cdot\left(75+25\right)\)

\(=89\cdot100\)

\(=8900\)

c) \(2^7:2^2+5^4:5^3\cdot2^4-3\cdot2^5\)

\(=2^{7-2}+5^{4-3}\cdot2^4-3\cdot2^5\)

\(=2^5+5\cdot2^4-3\cdot2^5\)

\(=2^4\cdot\left(2+5-3\cdot2\right)\)

\(=2^4\cdot\left(7-6\right)\)

\(=2^4\)

\(=16\)

d) \(100:\left\{250:\left[450-\left(4\cdot5^3-2^2\cdot25\right)\right]\right\}\)

\(=100:\left\{250:\left[450-\left(4\cdot5^3-4\cdot5^2\right)\right]\right\}\)

\(=100:\left[250:\left(450-4\cdot5^2\cdot4\right)\right]\)

\(=100:\left[250:\left(450-400\right)\right]\)

\(=100:\left(250:50\right)\)

\(=100:5\)

\(=20\)

Phạm Thuỳ Linh
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Phạm Thuỳ Linh
11 tháng 7 2016 lúc 17:25

312 + (146 -X ) =401

11- (15 + 21 ) + X- (25-9)

2- X +177 - (-5) 

X -12 = (-9) - 15 

Tran Dinh Phuoc Son
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