[x+p]²-[x+q]² =?【2x+y】²-【x+2y】²=?
2个回答

[x+p]²-[x+q]²

=[(x+p)+(x+q)][(x+p)-(x+q)]

=(x+p+x+q)(x+p-x-q)

=(2x+p+q)(p-q)

【2x+y】²-【x+2y】²

=[(2x+y)+(x+2y)][(2x+y)-(x+2y)]

=(3x+3y)(x-y)

=3(x+y)(x-y)

16【x+y】²-9【x-y】²

=[4(x+y)]²-[3(x-y)]²

=[4(x+y)+3(x-y)][4(x+y)-3(x-y)]

=(7x+y)(x+7y)

4【2x-3】²-x²

=[2(2x-3)]²-x²

=[2(2x-3)+x][2(2x-3)-x]

=(5x-6)(3x-6)

=3(5x-6)(x-2)