1231 nha bạn

bang 1231

1234 - 678 + 675=1231

k nha!

Giup minh voi!

\(1234 + 678 + 766 + 1322=(1234+766)+(678+1322)=2000+2000=4000\)

\(427\times42+427\times35+427\times23=427\times\left(42+35+23\right)=427\times100=42700\)

\(248\times125-248\times24-248=248\times\left(125-24-1\right)=248\times100=24800\)

A = 8 x 321 x 3 + 6 x 678 x 4 + 24  

A = 8 x 3 x 321 + 6 x 4 x 678 + 24 x 1

A = 24 x 321 + 24 x 678 + 24 x 1

A = 24 x ( 321 + 678 + 1 )

A = 24 x 1000

A = 24 000

B = 1234 x 6789 x (650 - 325 x 2 )

B = 1234 x 6789 x ( 650 - 650 )

B = 1234 x 6789 x 0

B = 0

A=(bấm máy tính)

A=24000

B=(bấm máy tính)

B=0

a)2008¹⁰⁰ + 2008⁹⁹ = 2008⁹⁹.(1 + 2008)=2008⁹⁹.2009 

Từ đó suy ra : 2008⁹⁹+2008¹⁰⁰ chia hết co 2009

b) 

12345⁶⁷⁸ - 12345⁶⁷⁷ = 12345⁶⁷⁷. ( 12345 - 1 ) = 12345⁶⁷⁷ . 12344

=> 12345⁶⁷⁸ - 12345⁶⁷⁷ chia hết cho 12344

k nha ><Thanks

Ta có: \(2008^{100}+2008^{99}=2008^{99}\left(2008+1\right)\)

                                               \(=2008^{99}.2009\)

Vậy \(2008^{100}+2008^{99}⋮2009\)

\(\text{–( –2019 + 2020 ) + (– 2019 ) – ( 1234 – 2020 ) }\)

\(=2019-2020-2019-1234+2020\)

\(=\left(2019-2019\right)+\left(-2020+2020\right)-1234\)

\(=0+0-1234=-1234\)

\(\text{– 25.800 .( – 0,04).1,25.2020}\)

\(=\left(-25\right).\left(-0,04\right).800.1,25.2020\)

\(=1.1000.2020=2020000\)

\(\text{( 5678 – 975 ) – (– 975 + 678 ) + 4000 }\)

\(=5678-975+975-678+4000\)

\(=\left(5678-678\right)+\left(-975+975\right)+4000\)

\(=5000+0+4000=9000\)

\(\text{– 78. (–245 ) + 245. 22}\)

\(=245.\left(78+22\right)\)

\(=245.100=24500\)

\(\text{765.( – 36) – 765. 64 }\)

\(=765.\left[\left(-36\right)-64\right]\)

\(=765.\left(-100\right)=-76500\)

\(\text{5632.121 + 5632 – 5632.22 }\)

\(=5632.\left(121+1-22\right)\)

\(=5632.100=563200\)

chúc bạn học tốt !!!!

678*678+320*678+678+678:2

=677661

@-@