\(\frac{7}{12}-\frac{2}{7}+\frac{1}{12}=\left(\frac{7}{12}+\frac{1}{12}\right)-\frac{2}{7}=\frac{2}{3}-\frac{2}{7}=\frac{14}{21}-\frac{6}{21}=\frac{8}{21}\)
\(\frac{7}{12}-\frac{2}{7}+\frac{1}{12}=\frac{7}{12}+\frac{1}{12}-\frac{2}{7}=\frac{8}{12}-\frac{2}{7}=\frac{2}{3}-\frac{2}{7}=\frac{14-6}{21}=\frac{8}{21}\)
\(\frac{7}{12}-\frac{2}{7}+\frac{1}{12}=\frac{8}{12}-\frac{2}{7}=\frac{2}{3}-\frac{2}{7}\)
\(=\frac{14}{21}-\frac{6}{21}\)\(=\frac{8}{21}\)
chúc bạn học tốt+-*/
7/12 - 2/7 + 1/12 = 49/84 - 24/84 + 1/12 = 25/84 + 1/12 = 25/84 + 7/84 = 32/84 = 8/21
Bước cuối là mình rút gọn nha
