1.(3x²-2y)(-3x²-2y)=___ 2.2009²-2008*2010(简便)

问题描述:

1.(3x²-2y)(-3x²-2y)=___ 2.2009²-2008*2010(简便)

(3x²-2y)(-3x²-2y)
=4y²-9x的四次方

2009²-2008*2010
=2009²-(2009-1)(2009+1)
=2009²-2009²+1
=1

1、(3x²-2y)(-3x²-2y)
=-(3x²-2y)(3x²+2y)
=-(9x²-4y²)
=4y²-9x⁴
2、2009²-2008*2010(简便)
=2009²-(2009-1)*(2009+1)
=2009²-(2009²-1)
=2009²-2009²+1
=1