(3x-4y)^2-(3x+4y)^2-(4x+3)(4x-3)
问题描述:
(3x-4y)^2-(3x+4y)^2-(4x+3)(4x-3)
答
(3x-4y)^2-(3x+4y)^2-(4x+3)(4x-3)
=(3x-4y+3x+4y)(3x-4y-3x-4y)-(16x^2-9)
=6x*(-8y)-16x^2+9
=-48xy-16x^2+9