1.2003^2-2004*2002
=2003^2-(2003+1)(2003-1)
=2003^2-(2003^2-1)
=1
2.打错了吧
应该是2ax^2-8axy+8ay^2-2a
=2a(x-2y)^2-2a
=2a-2a=0
3.a^2-b^2-c^2-2bc
=a^2-(b+c)^2
=(a+b+c)(a-b-c)
1.2003^2-2004*2002
=2003^2-(2003+1)(2003-1)
=2003^2-(2003^2-1)
=1
2.打错了吧
应该是2ax^2-8axy+8ay^2-2a
=2a(x-2y)^2-2a
=2a-2a=0
3.a^2-b^2-c^2-2bc
=a^2-(b+c)^2
=(a+b+c)(a-b-c)