\(A=\)\(\frac{6}{7}+\frac{1}{7}\times\frac{2}{7}+\frac{1}{7}\times\frac{5}{7}=\frac{6}{7}+\frac{1}{7}\left(\frac{2}{7}+\frac{5}{7}\right)\)
\(=\frac{6}{7}+\frac{1}{7}\times1\)
\(=\frac{6}{7}+\frac{1}{7}\)
\(=1\)
Cách 1: \(B=\frac{4}{9}\times\frac{13}{3}-\frac{4}{3}\times\frac{40}{9}\)
\(=\frac{52}{27}-\frac{160}{27}\)
\(=-4\)
K cho mk nhé thks bn nhiều
~CHÚC BẠN HỌC TỐT~
A=6/7+1/7(2/7+5/7)
=6/7+1/7.1
=6/7+1/7
=1
A=6/7+1/7.2/7+1/7.5/7
A=6/7+1/7.(2/7+5/7)
A=6/7+1/7.7/7
A=6/7+1/7.1
A=7/7=1
B=4/9.13/3-4/3.4/9
B=4/9.(13/3-4/3)
B=4/9.9/3
B=4/9.3
B=12/9
A=6/7+1/7.(2/7+5/7)=6/7+1/7.1=6/7+1/7=1
B=4/9.13/3-4/9.40/3=4/9.(13/3-40/3)=4/9.(-9)=-4