Question

分解因式（x^2+4y^2）^2-16x^2y^2

Answer 1

解
(x²+4y²)²-16x²y²
=(x²+4y²)²-(4xy)²
=[(x²+4y²)-4xy][(x²+4y²+4xy]
=(x-2y)²(x+2y)²

Answer 2

﹙x²＋4y²﹚²－16x²y²
=﹙x²＋4y²﹚²－﹙4xy﹚²
=[﹙x²＋4y²﹚＋4xy][﹙x²＋4y²﹚－4xy]
=﹙x²＋4xy＋4y²﹚﹙x²－4xy＋4y²﹚
=﹙x＋2y﹚²﹙x－2y﹚²