问题 解答题
约分:
(1)
-35a4b3c
21a2b4d

(2)
x2-(y-z)2
(x+y)2-z2
答案

(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

选择题
单项选择题 A1/A2型题