计算:(x+2y-3)(x-2y+3)

2025-06-21 15:46:10
推荐回答(1个)
回答1:

(x+2y-3)(x-2y+3)
=[x+(2y-3)][x-(2y-3)]
=x²-(2y-3)²
=x²-(4y²-12y+9)
=x²-4y²+12y-9