Question

\(\dfrac{-7}{19}.\dfrac{8}{11}-\dfrac{7}{11}.\dfrac{3}{19}-\dfrac{12}{19}\)

Tính nhanh

Answer 1

\(=\dfrac{-7\cdot8-7\cdot3}{11\cdot19}-\dfrac{12}{19}=\dfrac{-7}{19}-\dfrac{12}{19}=-1\)

Answer 2

\(=\dfrac{7}{19}.\dfrac{-8}{11}-\dfrac{7}{19}.\dfrac{3}{11}-\dfrac{12}{19}=\dfrac{7}{19}.\left(-\dfrac{8}{11}-\dfrac{3}{11}\right)-\dfrac{12}{19}=\dfrac{7}{19}.\left(-1\right)-\dfrac{12}{19}=-\dfrac{7}{19}-\dfrac{12}{19}=-\dfrac{19}{19}=-1\)