ta có: \(M=\frac{7.9+14.27+21.36}{21.27+42.81+63.108}\)

\(M=\frac{7.9+7.2.9.3+7.3.9.4}{21.27+21.227.3+21.3.27.4}\)

\(M=\frac{7.9.\left(1+2.3+3.4\right)}{21.27.\left(1+2.3+3.4\right)}\)

\(M=\frac{7.9}{3.7.3.9}\)

\(M=\frac{1}{3^2}\)

\(M=\frac{1}{9}\)

và \(N=\frac{37}{333}=\frac{37}{37.9}=\frac{1}{9}\)

\(N=\frac{1}{9}\)

\(\Rightarrow M=N\left(=\frac{1}{9}\right)\)

M= \(\frac{7.9+14.27+21.36}{21.27+42.81+63.108}\).

M= \(\frac{7.9+14.27+21.36}{7.3.9.3+14.3.27.3+21.3+36.3}\).

M= \(\frac{7.9+14.27+21.36}{7.9.9+14.27.9+21.36.9}\).

M= \(\frac{7.9+14.27+21.36}{9\left(7.9+14.27+21.36\right)}\).

M= \(\frac{1}{9}\).

Ta có: N= \(\frac{37}{333}\)= \(\frac{1}{9}\).

Vì \(\frac{1}{9}\)= \(\frac{1}{9}\) nên M= N.

Vậy M= N.

a: \(M=\frac{53\cdot71-18}{71\cdot52+53}\)

\(=\frac{71\cdot52+71-18}{71\cdot52+53}=\frac{71\cdot52+53}{71\cdot52+53}=1\)

\(N=\frac{54\cdot107-53}{53\cdot107+54}\)

\(=\frac{53\cdot107+107-53}{53\cdot107+54}=\frac{53\cdot107+54}{53\cdot107+54}\)

=1

=>M=N

b: \(A=\frac{7\cdot9+14\cdot27+21\cdot36}{21\cdot27+42\cdot81+63\cdot108}\)

\(=\frac{7\cdot9\cdot\left(1+2\cdot3+3\cdot4\right)}{21\cdot27\cdot\left(1+2\cdot3+3\cdot4\right)}=\frac{7}{21}\cdot\frac{9}{27}=\frac13\cdot\frac13=\frac19\)

\(B=\frac{37}{333}=\frac{37}{37\cdot9}=\frac19\)

Do đó: A=B

Rút gọn tử số và mẫu số, ta được:
1.1+1.1+1.1/3.3+3.3+3.3
=1.3/9.3
Rút gọn 3 trên tử với 3 dưới mẫu
Vậy A=1/9

Tick nhé 

alo làm giống vcl

A = \(\frac{7.9+2.7.3.9-3.7.4.9}{3.7.3.9+2.3.7.9.9+7.9.4.3.9}\)

= \(\frac{7.9.\left(1+6-12\right)}{3.7.9.\left(3+18+36\right)}=\frac{-5}{3.57}=\frac{-5}{171}\)

sai roi

1/3

A = \(\dfrac{7.9+14.27+21.36}{21.27+42.81+63.108}\)

= \(\dfrac{7.9+7.2.9.3+7.3.9.4}{21.27+21.2.27.3+21.3.27.4}\)

= \(\dfrac{\left(7.9\right)\left(2.3+3.4\right)}{\left(21.27\right)\left(2.3+.3.4\right)}\)

= \(\dfrac{1}{9}\)

@Nguyễn Ngọc Gia Hân

Bạn Khánh Linh làm sai kìa !

kết quả là 1/9

\(A=\frac{7.9+14.27+21.36}{21.27+42.81+63.108}\)

\(A=\frac{7.9+7.2.9.3+7.3.9.4}{21.27+21.2.27.3+21.3.27.4}\)

\(A=\frac{7.9.\left(1+2.3+3.4\right)}{21.27+\left(1+2.3+3.4\right)}\)

\(A=\frac{7.9}{3.7.3.9}\)

\(A=\frac{1}{3.3}=\frac{1}{9}\)