Question

高手帮忙以下的因式分解啊 6m^2+mn-2n^2-10m-9n-4

最好有过程

Answer 1

解法一:
原式可看作m的二次式,
故可以如下按m的降幂排列,
得到:
6m^2+mn-2n^2-10m-9n-4
=6m^2
+
(n-10)m
+
(-2n^2-9n-4)
=6m^2
+
(n-10)m
-
(2n+1)(n+4)
注意到
(2n+1)*2
与
(n+4)*3
之差正好是n-10,
得到
=
[2m
-
(n+4)][3m
+
(2n+1)]
=
(2m-n-4)(3m+2n+1)