﹙3m-2n+p)(3m+2n-p)
=[3m-﹙2n-p)][3m+﹙2n-p﹚]
=9m²-﹙2n-p﹚²
=9m²-﹙4n²-4np+p²﹚
=9m²-4n²+4np-p²
不知我猜得对吗如果对请采纳