3⁷ x 7 + 2³ x 10 - 81: 9

= 15309  + 80 - 9

= 15380

37 x 7 + 23 x 10 - 81: 9

= 15309  + 80 - 9

= 15380

    12x7x5 + 35 x1822 - 5x94x7

=  12x35 + 35 x 1822 - 35x94

= 35 x ( 12 + 1822 - 94)

= 35 x 1740

= 60900

1 x 2 x 3 x .....x 1000 x ( 456 x 789789 - 789 x 456456)

 = 1x2x3x.....x1000x ( 456 x 789 x 1001 - 789 x 456 x 1001)

= 1x2x3x4x.....x1000 x 0

= 0 

`(1 xx 2 xx 3 xx .....xx 1000) xx ( 456 xx 789789 - 789 xx 456456)

` = (1xx2xx3xx.....xx1000)xx ( 456 xx 789 xx 1001 - 789 xx 456 xx 1001)`

`= (1xx2xx3xx4xx.....xx1000) xx 0`

`= 0`

x = -2,5

nhanh mik can gap

(x-2)² = \(\dfrac{9}{25}\) 

(x-2)² = ( \(\dfrac{3}{5}\))²

x - 2 = \(\dfrac{3}{5}\)

x = \(\dfrac{3}{5}\) + 2

x =  13/5

A = {0; 3; 6; 9; 12; 15;.........99}

tổng của tất cả các phần tử của tập A là

B = 0 + 3 + 6 + 9 + 99

B = ( 0 + 99){ ( 99 -0): 3 + 1 } : 2 = 1683

3²⁰⁰ = (3²)¹⁰⁰  =9¹⁰⁰> 8¹⁰⁰ = (2³)¹⁰⁰  = 2³⁰⁰ vậy 3²⁰⁰ > 2³⁰⁰

tách \(3^{200}\)=\(3^{2.100}\)=\(\left(3^2\right)^{100}\)=\(9^{100}\)

\(2^{300}\)=\(2^{3.100}\)=\(\left(2^3\right)^{100}\)=\(8^{100}\)

mà \(9^{100}\)>\(8^{100}\)

=> \(3^{200}\)>\(2^{300}\)

2( \(\dfrac{1}{2}\) x - \(\dfrac{1}{3}\)) - \(\dfrac{3}{2}\) = \(\dfrac{1}{4}\)

2(\(\dfrac{1}{2}\)x - \(\dfrac{1}{3}\))  = \(\dfrac{1}{4}\) + \(\dfrac{3}{2}\)

2(\(\dfrac{1}{2}\)x - \(\dfrac{1}{3}\)) = \(\dfrac{7}{4}\)

\(\dfrac{1}{2}\)x = \(\dfrac{7}{4}\) : 2 + \(\dfrac{1}{3}\)

\(\dfrac{1}{2}\)x = \(\dfrac{29}{24}\)

x = \(\dfrac{29}{24}\) x2

x = \(\dfrac{29}{12}\)

`2.(1/2 x - 1/3) - 3/2 = 1/4`

`2.(1/2 x - 1/3) = 1/4 + 3/2`

`2.(1/2 x - 1/3) = 1/4 + 6/4`

`2.(1/2 x - 1/3) = 7/4`

`1/2x - 1/3 = 7/4 : 2`

`1/2 x - 1/3 = 7/4 xx 1/2`

`1/2 x - 1/3 = 7/8`

`1/2 x  = 7/8 + 1/3`

`1/2 x = 21/28 + 7/28`

`1/2 x = 29/24`

`x=29/24 : 1/2`

`x=29/24 xx 2`

`x=29/12`

Vậy `x = 29/12`

          A   = 1 +  2 + 2² + 2³+......+2⁹

         2A  =       2+ 2² + 2³ +.......+2⁹ + 2¹⁰

    2A - A  =      2¹⁰ -1

          A  =     2¹⁰ - 1

11+12+123=123553444

Ta có:

218 = 23.215 = 8.215 > 7.215

=> 218 > 7.215

67+80=169789765