\(24\cdot(34-19)-34\cdot(24-19)\)
\(=24\cdot34-24\cdot19-34\cdot24-34\cdot19\)
\(=(24\cdot34-34\cdot24)-(24\cdot19-34\cdot19)\)
\(=0-(-190)=190\)
Cách 1 :24.(34-19)-34.(24-19) =24.15-34.5
=360-170
=190
Cách 2 :24.(34-19)-34.(24-19) =24.34-24.19-34.24+34.19
=816-456-816+646
=360-816+646
=-456+646
=190