(x+2y)²(x²+4y²)²(x-2y)²-(x四次方-2y四次方)² 急
2个回答

原式=[(x+2y)(x-2y)]²(x²+4y²)²-(x四次方-2y四次方)²

=(x²-4y²)²(x²-4y²)²-(x四次方-2y四次方)²

=(x四次方-16y四次方)²-(x四次方-2y四次方)²

=[(x四次方-16y四次方)-(x四次方-2y四次方)]×[(x四次方-16y四次方)+(x四次方-2y

四次方)]

=-14y四次方(2x四次方-18y四次方)