a²-b²-c²+2ab等于几
问题描述:
a²-b²-c²+2ab等于几
答
a²+b²-c²+2ab
=(a+b)²-c²
=(a+b+c)(a+b-c)
a²-b²-c²+2ab等于几
a²+b²-c²+2ab
=(a+b)²-c²
=(a+b+c)(a+b-c)