3/7 + 4/9 + 5/11 + 8/14 + 10/18 + 12/22
= 3/7 + 4/9 + 5/11 + 4/7 + 5/9 + 6/11
= ( 3/7 + 4/7 ) + ( 4/9 + 5/9 ) + ( 5/11 + 6/11 )
= 7/7 +9/9 + 11/11
= 1 + 1 + 1
= 3
tk mk nha , cảm ơn ạ , được ko á ?????????
3/7 + 4/9 + 5/11 + 8/14 + 10/18 + 12/22 = 3
\(\frac{3}{7}\)+ \(\frac{4}{9}\)+ \(\frac{5}{11}\)+ \(\frac{8}{14}\)+ \(\frac{10}{18}\)+ \(\frac{12}{22}\)
= \(\frac{55}{63}\)+ \(\frac{5}{11}\)+ \(\frac{8}{14}\)+ \(\frac{10}{18}\)+ \(\frac{12}{22}\)
= \(\frac{920}{693}\)+ \(\frac{8}{14}\)+ \(\frac{10}{18}\)+ \(\frac{12}{22}\)
= \(\frac{188}{99}\)+ \(\frac{10}{18}\)+ \(\frac{12}{22}\)
= \(\frac{27}{11}\)+ \(\frac{12}{22}\)
= \(3\)
\(\frac{3}{7}+\frac{4}{9}+\frac{5}{11}+\frac{8}{14}+\frac{10}{18}+\frac{12}{22}\)
\(\frac{3}{7}+\frac{4}{9}+\frac{5}{11}+\frac{4}{7}+\frac{5}{9}+\frac{6}{11}\)
=\(\left(\frac{3}{7}+\frac{4}{7}\right)+\left(\frac{4}{9}+\frac{5}{9}\right)+\left(\frac{5}{11}+\frac{6}{11}\right)\)
=\(\frac{7}{7}+\frac{9}{9}+\frac{11}{11}\)
=1 + 1 + 1
=3
3/7 + 4/9 + 5/11 + 8/14 + 10/18 + 12/22
= 3/7+4/9+5/11 + 4/7 + 5/9 + 6/11
= ( 3/7 + 4/9 ) + ( 4/9 + 5/9 ) + ( 5/11 + 6/11 )
= 7/7 9/9 + 11/11
= 1+1+1
= 3
\(=\left(\frac{3}{7}+\frac{8}{14}\right)+\left(\frac{4}{9}+\frac{10}{18}\right)+\left(\frac{5}{11}+\frac{12}{22}\right)\)
\(=\left(\frac{6}{14}+\frac{8}{14}\right)+\left(\frac{8}{18}+\frac{10}{18}\right)+\left(\frac{10}{22}+\frac{12}{22}\right)\)
\(=\frac{14}{14}+\frac{18}{18}+\frac{22}{22}\)
\(=1+1+1=3\)
\(\frac{3}{7}+\frac{4}{9}+\frac{5}{11}+\frac{8}{14}+\frac{10}{18}+\frac{12}{22}\)
\(=\frac{3}{7}+\frac{4}{9}+\frac{5}{11}+\frac{4}{7}+\frac{5}{9}+\frac{6}{11}\)
\(=\left(\frac{3}{7}+\frac{4}{7}\right)+\left(\frac{4}{9}+\frac{5}{9}\right)+\left(\frac{5}{11}+\frac{6}{11}\right)\)
\(=\frac{7}{7}+\frac{9}{9}+\frac{11}{11}\)
\(=1+1+1\)
\(=3\)