5436*5438-5435*5439 用简便方法算
问题描述:
5436*5438-5435*5439 用简便方法算
答
5436*5438-5435*5439
= (5437-1)(5437+1) - (5437-2)(5437+2)
= 5437^2 - 1 - 5437^2 +4
=3