(1)当a=102,b=98时,求a²-b²的值 (2)计算:2004²-2004乘2003
问题描述:
(1)当a=102,b=98时,求a²-b²的值 (2)计算:2004²-2004乘2003
答
a²-b²
=(a+b)(a-b)
=(102+98)(102-98)
=200*4
=800
2004²-2004乘2003
=2004*(2004-2003)
=2004*1
=2004