用简便方法计算:(a+b+c)^2

2025-03-22 11:09:28
推荐回答(1个)
回答1:

(a+b+c)²
=[(a+b)+c]²
=(a+b)²+2(a+b)c+c²
=a²+2ab+b²+2ac+2bc+c²
=a²+b²+c²+2ab+2bc+2ac