题目内容：

因式分解4x^2y^2+9+8xy-x^2-4y^2

优质解答

4x^2y^2+9+8xy-x^2-4y^2
=(4x^2y^2+9+12xy)-x^2-4y^2-4xy
=(2xy+3)²-(x+2y)²
=(2xy+x+2y+3)(2xy-x-2y+3)