3 (a的平方-2a-3) -5 (-5a的平方+a- 2)=
问题描述:
3 (a的平方-2a-3) -5 (-5a的平方+a- 2)=
答
3 (a的平方-2a-3) -5 (-5a的平方+a- 2)
=3a²-6a-9+25a²-5a+10
=28a²-11a+1
=(4a-1)(7a-1)