Question

[Nguyễn Quỳnh Như]

1. 2². 3 - {1mu 10 + 8 } : 3
2. 1 + 6 + 11 + ...... + 2001 + 2008
3. 6 mu 2 : 4 . 3 + 2. 5 mu 2
4. 4.{3x - 4 } - 2 = 18
5. { 105 - x } : 2⁵ = 3⁰+ 1
6. 2x - 138 = 2². 3²
7. {6x - 39 } . 28 = 5628
8. { 9x + 2 } . 3 = 60
9. { 26 - 3x } : 5 + 71 = 75
10. 5^x + 1= 125

• cho S = 2⁰+ 2 + 2 mu 2 + 2 mu 3 + ........ + 2 ^​23
• ^{chung minh rang S chia het cho 3}
• ^{chung minh rang S chia het cho 7}

Answer 1

[Lùn Tè]

1,2,3 ko bt lm nhé

4. \(4\cdot\left(3x-4\right)-2=18\\ 12x-16-2-18=0\\ 12x=-36\\ x=-2\)

5. ( 105-x)/2⁵=3⁰+1

(105-x) / 32 = 1+1

( 105-x) / 32 = 2

105-x=64

x=105-64

x=41

6. 2x - 138=2²*3²

2x-138=36

2x=138+36

2x=174

x=87

7.(6x-39)*28=5628

6x-39=201

6x=240

x=40

8. (9x+2)*3=60

9x+2=20

9x=18

x=2

9. (26-3x)/5+71=75

(26-3x) /5=4

26-3x = 20

3x=6

x=2