问题
填空题
计算:(2m+1)(1-2m)=______;(3a-2b)•______=4b2-9a2.
答案
(2m+1)(1-2m)=12-(2m)2=1-4m2,
(3a-2b)(-2b-3a)=(-2b)2-(3a)2=4b2-9a2,
故答案为:1-4a2,(-2b-3a).
计算:(2m+1)(1-2m)=______;(3a-2b)•______=4b2-9a2.
(2m+1)(1-2m)=12-(2m)2=1-4m2,
(3a-2b)(-2b-3a)=(-2b)2-(3a)2=4b2-9a2,
故答案为:1-4a2,(-2b-3a).