计算下列各题:
(1)-10a5b3c÷5a4b;
(2)(12a3-6a2+3a)÷3a;
(3)(x-y)(x+2y).
(1)原式=[(-10)÷5]a5-4b3-1c
=-2ab2c;
(2)原式=12a3÷3a-6a2÷3a+3a÷3a
=4a2-2a+1;
(3)原式=x2-xy+2xy-2y2
=x2+xy-2y2.
计算下列各题:
(1)-10a5b3c÷5a4b;
(2)(12a3-6a2+3a)÷3a;
(3)(x-y)(x+2y).
(1)原式=[(-10)÷5]a5-4b3-1c
=-2ab2c;
(2)原式=12a3÷3a-6a2÷3a+3a÷3a
=4a2-2a+1;
(3)原式=x2-xy+2xy-2y2
=x2+xy-2y2.