(5x+3y)^2-(5x-3y)^2 (逆用平方差公式)
问题描述:
(5x+3y)^2-(5x-3y)^2 (逆用平方差公式)
(5x+3y)^2-(5x-3y)^2 (逆用平方差公式)
答
(5x+3y)^2-(5x-3y)^2
=(5x+3y+5x-3y)(5x+3y-5x+3y)
=10x*6y
=60xy