Thực hiện phép tính: a) -1/3 a^2b ( -6ab^2 -3a +9b^3) ;
Giải thích
a) −13a2b(−6ab2−3a+9b3)
=−13a2b . (−6ab2)−−13a2b . 3a+−13a2b . 9b3
=13a2b . 6ab2+13a2b . 3a−13a2b . 9b3
= 2a3b3 + a3b – 3a2b4;
a) −13a2b(−6ab2−3a+9b3)
=−13a2b . (−6ab2)−−13a2b . 3a+−13a2b . 9b3
=13a2b . 6ab2+13a2b . 3a−13a2b . 9b3
= 2a3b3 + a3b – 3a2b4;