so sánh

a,\(\frac{6}{7}...\frac{12}{14}\)

\(\frac{6}{7}=\frac{6.2}{7.2}=\frac{12}{14}\) 

\(\Rightarrow\frac{12}{14}=\frac{12}{14}\)

\(\Rightarrow\frac{6}{7}=\frac{12}{14}\)

b,\(\frac{2}{3}...\frac{3}{4}\)

\(\frac{2}{3}=\frac{2.4}{3.4}=\frac{8}{12}\)

\(\frac{3}{4}=\frac{3.3}{4.3}=\frac{9}{12}\)

\(\Rightarrow\frac{8}{12}< \frac{9}{12}\)

\(\Rightarrow\frac{2}{3}< \frac{3}{4}\)

\(\frac{6}{7}\)\(=\)\(\frac{12}{14}\)

\(\frac{2}{3}\)\(>\)\(\frac{3}{4}\)

bn có cần giải ra luôn để bn dễ hiểu ko

/

a)\(\frac{12}{14}=\frac{6}{7}\)

=>\(\frac{6}{7}=\frac{7}{6}\)

b)

\(\frac{2}{3}< \frac{3}{4}\)

okey cô bn

ta quy đồng 2 mẫu số

a. \(\frac{6}{7}=\frac{6.2}{7.2}=\frac{12}{14}\)

b. 2/3=8/12

3/4=9/12 

=> 2/3<3/4

nhầm CMNR

\(\frac{6}{7}=\frac{12}{14}\)

\(\frac{2}{3}< \frac{3}{4}\)

nhìn nhầm thành \(\frac{3}{2}\)

ta có

\(\frac{12}{14}=\frac{12:2}{14:2}=\frac{6}{7}\)

=>6/7=6/7

vậy 6/7=12/14

b)ta có

\(\frac{2}{3}=\frac{2\cdot4}{3\cdot4}=\frac{8}{12}\)

\(\frac{3}{4}=\frac{3\cdot3}{4\cdot3}=\frac{9}{12}\)

=>8/12<9/12

vậy 2/3<3/4

câu a) giải ùi nhé

câu b)

\(\frac{2}{3}=\frac{2x4}{3x4}=\frac{8}{12}\)

\(\frac{3}{4}=\frac{3x3}{4x3}=\frac{9}{12}\)

=>\(\frac{2}{3}< \frac{3}{4}\)