a) 15243 + 2643 + 27364 - 643 + 4757 - 736= 42000

b) 234 + 13 + 355 + 2345 +266 -513 = (234 +266 ) +(355+2345) +13 - 513 = 500 + 2700 + 13 - 513 = 3200 + 13 - 513 = 2700

c) (56 x 27 + 56 x 35 ) : 62 = [56x (27 + 35)] : 62 = 56 x 62 : 62 =56

K chị nha

x^5-(x+1)x^4+(x+1)x^3-(x+1)x^2+(x+1)x-(x+1)

tự làm tiếp đi

1234567890-12345

2345 x 25 + 2345 x 75 + 2345

= 2345 x (25+75+1)

= 2345 x 101

=236845

\(=2345\times\left(25+75+1\right)\)
\(=2345\times101\)
\(=236845\)

=236845

`2345 x 25 x 2345 x 74 + 2345`

`= 2345 x ( 25 + 74 + 1 )`

`= 2345 x 100 `

`= 234 500`

234500

`2345 x 25 x 2345 x 74 + 2345`

`= 2345 x ( 25 + 74 + 1 )`

`= 2345 x 100 `

`= 234 500`

học tốt

a,2643 dm³=.............2,643....................... m³

 b. Tính : 

354dm³ + 330000cm³ × 2

=354dm³ + 330dm³ x 2

=1014 dm³

a. 2,643m³
b.1014 dm³

a. 2,643m³
b.1014 dm^3\

2345 x 25 x 2345 x 74 + 2345

= 2345 x ( 25 + 74 + 1 )

= 2345 x 100 = 234 500

2345 x 25 x 2345 x74 +2345 

=2345  x 25 x2345 x 74 +2345 x 1

= 2345 x ( 25+74 +1 )

=2345 x 100

=234500

`2345 x 25 x 2345 x 74 + 2345`

`= 2345 x ( 25 + 74 + 1 )`

`= 2345 x 100 `

`= 234 500`

\(=2345\left(7+13+80\right)+7655\left(24+25+51\right)=10000\cdot100=1000000\)