Giải:
\(\dfrac{13}{9}.\dfrac{15}{4}-\dfrac{7}{9}.\dfrac{13}{4}-\dfrac{5}{9}.\dfrac{13}{4}\)
\(=\dfrac{13}{9}.\dfrac{15}{4}-\dfrac{13}{9}.\dfrac{7}{4}-\dfrac{13}{9}.\dfrac{5}{4}\)
\(=\dfrac{13}{9}.\left(\dfrac{15}{4}-\dfrac{7}{4}-\dfrac{5}{4}\right)\)
\(=\dfrac{13}{9}.\dfrac{3}{4}\)
\(=\dfrac{13}{12}\)
Chúc bạn học tốt!
Hoặc bạn cx có thể lm thế này:
Giải:
\(\dfrac{13}{9}.\dfrac{15}{4}-\dfrac{7}{9}.\dfrac{13}{4}-\dfrac{5}{9}.\dfrac{13}{4}\)
\(=\dfrac{15}{9}.\dfrac{13}{4}-\dfrac{7}{9}.\dfrac{13}{4}-\dfrac{5}{9}.\dfrac{13}{4}\)
\(=\dfrac{13}{4}.\left(\dfrac{15}{9}-\dfrac{7}{9}-\dfrac{5}{9}\right)\)
\(=\dfrac{13}{4}.\dfrac{1}{3}\)
\(=\dfrac{13}{12}\)
Chúc bạn học tốt!
