(3x+3y-2)(3x-3y-2) 计算
问题描述:
(3x+3y-2)(3x-3y-2) 计算
答
(3x+3y-2)(3x-3y-2)
=[(3x-2)+3y] [(3x-2)-3y]
=(3x-2)^2-3y^2
=9x^2-12x+4-9y^2
答
(3x+3y-2)(3x-3y-2)
=(3x-2)(3x-2)-(3y*3y)
=9x*x-9y*y-12x+4
答
(3x+3y-2)(3x-3y-2)
=((3x-2)+3y)((3x-2-)3y)
=9x²-12x+4-9y²
答
=(3x-2+3y)(3x-2-3y)=(3x-2)^2-(3y)^2=9x^2+4-12x-9y^2