4(x+y)^2-(2x+5)(2x-5)
问题描述:
4(x+y)^2-(2x+5)(2x-5)
2a^3x^2-8a^3y^2
答
=4(x²+2xy+y²)-(4x²-25)
=(4x²-4x)+8xy+4y²+25
=8xy+4y²+25
=2a³(x²-4y²)
=2a³(x-2y)(x+2y)