问题
填空题
(3x+2y)2-(3x-2y)2=______.
答案
(3x+2y)2-(3x-2y)2,
=(3x+2y+3x-2y)(3x+2y-3x+2y),
=6x•4y,
=24xy;
故填24xy.
(3x+2y)2-(3x-2y)2=______.
(3x+2y)2-(3x-2y)2,
=(3x+2y+3x-2y)(3x+2y-3x+2y),
=6x•4y,
=24xy;
故填24xy.