原式=[(2x)^2-(3y)^2](3y-2x)+9(2x+3y)^3
=-(2x+3y)(2x-3y)^2+9(2x+3Y)^3
=(2x+3y)[3^2(2x+3y)^2-(2x-3y)^2]
=(2x+3y)(6x+9y+2x-3y)(6x+9y-2x+3y)
=8(2x+3y)(4x+3y)(x+3y)
原式=[(2x)^2-(3y)^2](3y-2x)+9(2x+3y)^3
=-(2x+3y)(2x-3y)^2+9(2x+3Y)^3
=(2x+3y)[3^2(2x+3y)^2-(2x-3y)^2]
=(2x+3y)(6x+9y+2x-3y)(6x+9y-2x+3y)
=8(2x+3y)(4x+3y)(x+3y)