约分: (1)−35a4b3c21a2b4d, (2)x2−(y−z)2(x+y)2−z2.

问题描述:

约分:
(1)

−35a4b3c
21a2b4d

(2)
x2(y−z)2
(x+y)2z2

(1)原式=

−7a2b3•5a2c
7a2b3•3bd
=-
5a2c
3db

(2)原式=
(x+y−z)(x−y+z)
(x+y+z)(x+y−z)
=
x−y+z
x+y+z