17.( 85+15)-120=15.100-120=1500 -120=1380

Bạn gom số lại là được nhé tick nhé

Lời giải:
\(M=\frac{9^4.27^5.3^6.3^4}{3^8.81^4.234.8^2}=\frac{(3^2)^4.(3^3)^5.3^6.3^4}{3^8.(3^4)^4.2.3^2.13.(2^3)^2}\)

\(=\frac{3^8.3^{15}.3^6.3^4}{3^8.3^{16}.2.3^2.13.2^6}=\frac{3^{33}}{3^{26}.2^7.13}=\frac{3^7}{2^7.13}\)

1428:{23-[(8.81-369):31]}

= 1428 : { 23 - [ 279 : 31 ] }

= 1428 : { 23 - 9 }

= 1428 : 14

= 102

1428:{23-[(8.81-369):31]}

=1428:{23-[(648-369):31]}

=1428:{23-[279:31]}

=1428:{23-9}

=1428:14

=102

Học tốt~

\(=\dfrac{\left(2^3\right)^3.\left(3^2\right)^4-2^8.\left(3^4\right)^2}{\left(2^4\right)^2.\left(3^4\right)^2+\left(2^2\right)^4.\left(3^3\right)^3}=\dfrac{2^9.3^8-2^8.3^8}{2^8.3^8+2^8.3^9}=\)

\(=\dfrac{2^8.3^8.\left(2-1\right)}{2^8.3^8.\left(1+3\right)}=\dfrac{1}{4}\)

2.31.12+4.6.42+8.27.3

= (2.12).31+(4.6).42+(8.3).27

= 24.31+24.42+24.27

= 24.(31+42+27)

 = 24.100

= 2400

_HT_

2.31.12+4.6.42+8.27.3

=24.31+24.42+27.24

=24.(31+42+27)

=24.100

=2400

2.31.12+4.6.42+8.27.3 = 24x31+24x42+24x27=24x(31+42+27)=24x100=2400 nha Dương Ngọc Phuong Linh

2.31.12 + 4.6.42 + 8.27.3

= ( 2.12). 31 + ( 4. 6).42 + (8.3). 27

= 24.31 + 24.42 + 24.27

= 24.(31 + 42 + 27) = 24.100 = 2400